Index: Makefile.in
==================================================================
--- Makefile.in
+++ Makefile.in
@@ -560,11 +560,12 @@
 #
 TESTOPTS = --verbose=file --output=test-out.txt
 
 # Extra compiler options for various shell tools
 #
-SHELL_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_FTS5
+SHELL_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS4
+SHELL_OPT += -DSQLITE_ENABLE_EXPLAIN_COMMENTS
 FUZZERSHELL_OPT = -DSQLITE_ENABLE_JSON1
 FUZZCHECK_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_MEMSYS5
 
 # This is the default Makefile target.  The objects listed here
 # are what get build when you type just "make" with no arguments.
@@ -585,13 +586,13 @@
 	$(LTLINK) -no-undefined -o $@ tclsqlite.lo \
 		libsqlite3.la @TCL_STUB_LIB_SPEC@ $(TLIBS) \
                 -rpath "$(TCLLIBDIR)/sqlite3" \
 		-version-info "8:6:8"
 
-sqlite3$(TEXE):	$(TOP)/src/shell.c libsqlite3.la sqlite3.h
+sqlite3$(TEXE):	$(TOP)/src/shell.c sqlite3.c
 	$(LTLINK) $(READLINE_FLAGS) $(SHELL_OPT) -o $@ \
-		$(TOP)/src/shell.c libsqlite3.la \
+		$(TOP)/src/shell.c sqlite3.c \
 		$(LIBREADLINE) $(TLIBS) -rpath "$(libdir)"
 
 sqldiff$(TEXE):	$(TOP)/tool/sqldiff.c sqlite3.c sqlite3.h
 	$(LTLINK) -o $@ $(TOP)/tool/sqldiff.c sqlite3.c $(TLIBS)
 
@@ -1165,14 +1166,19 @@
 #
 checksymbols: sqlite3.lo
 	nm -g --defined-only sqlite3.o | grep -v " sqlite3_" ; test $$? -ne 0
 	echo '0 errors out of 1 tests'
 
-# Build the amalgamation-autoconf package.
+# Build the amalgamation-autoconf package.  The amalamgation-tarball target builds
+# a tarball named for the version number.  Ex:  sqlite-autoconf-3110000.tar.gz.
+# The snapshot-tarball target builds a tarball named by the SHA1 hash
 #
 amalgamation-tarball: sqlite3.c
-	TOP=$(TOP) sh $(TOP)/tool/mkautoconfamal.sh
+	TOP=$(TOP) sh $(TOP)/tool/mkautoconfamal.sh --normal
+
+snapshot-tarball: sqlite3.c
+	TOP=$(TOP) sh $(TOP)/tool/mkautoconfamal.sh --snapshot
 
 # The next two rules are used to support the "threadtest" target. Building
 # threadtest runs a few thread-safety tests that are implemented in C. This
 # target is invoked by the releasetest.tcl script.
 # 

Index: Makefile.msc
==================================================================
--- Makefile.msc
+++ Makefile.msc
@@ -124,16 +124,16 @@
 #
 !IFNDEF FOR_WINRT
 FOR_WINRT = 0
 !ENDIF
 
-# Set this non-0 to compile binaries suitable for the UAP environment.
+# Set this non-0 to compile binaries suitable for the UWP environment.
 # This setting does not apply to any binaries that require Tcl to operate
 # properly (i.e. the text fixture, etc).
 #
-!IFNDEF FOR_UAP
-FOR_UAP = 0
+!IFNDEF FOR_UWP
+FOR_UWP = 0
 !ENDIF
 
 # Set this non-0 to compile binaries suitable for the Windows 10 platform.
 #
 !IFNDEF FOR_WIN10
@@ -412,12 +412,12 @@
 TCC = $(CC) -nologo -W4 -DINCLUDE_MSVC_H=1 $(CCOPTS) $(TCCOPTS)
 !ELSE
 TCC = $(CC) -nologo -W3 $(CCOPTS) $(TCCOPTS)
 !ENDIF
 
-TCC = $(TCC) -DSQLITE_OS_WIN=1 -I$(TOP) -I$(TOP)\src -fp:precise
-RCC = $(RC) -DSQLITE_OS_WIN=1 -I$(TOP) -I$(TOP)\src $(RCOPTS) $(RCCOPTS)
+TCC = $(TCC) -DSQLITE_OS_WIN=1 -I. -I$(TOP) -I$(TOP)\src -fp:precise
+RCC = $(RC) -DSQLITE_OS_WIN=1 -I. -I$(TOP) -I$(TOP)\src $(RCOPTS) $(RCCOPTS)
 
 # Adjust the names of the primary targets for use with Windows 10.
 #
 !IF $(FOR_WIN10)!=0
 SQLITE3DLL = winsqlite3.dll
@@ -549,12 +549,12 @@
 !ENDIF
 
 # C compiler options for the Windows 10 platform (needs MSVC 2015).
 #
 !IF $(FOR_WIN10)!=0
-TCC = $(TCC) /guard:cf -D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE
-BCC = $(BCC) /guard:cf -D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE
+TCC = $(TCC) /d2guard4 -D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE
+BCC = $(BCC) /d2guard4 -D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE
 !ENDIF
 
 # Also, we need to dynamically link to the correct MSVC runtime
 # when compiling for WinRT (e.g. debug or release) OR if the
 # USE_CRT_DLL option is set to force dynamically linking to the
@@ -905,23 +905,23 @@
 LTLINKOPTS = $(LTLINKOPTS) /DYNAMICBASE
 LTLINKOPTS = $(LTLINKOPTS) WindowsPhoneCore.lib RuntimeObject.lib PhoneAppModelHost.lib
 LTLINKOPTS = $(LTLINKOPTS) /NODEFAULTLIB:kernel32.lib /NODEFAULTLIB:ole32.lib
 !ENDIF
 
-# When compiling for UAP or the Windows 10 platform, some extra linker
+# When compiling for UWP or the Windows 10 platform, some extra linker
 # options are also required.
 #
-!IF $(FOR_UAP)!=0 || $(FOR_WIN10)!=0
+!IF $(FOR_UWP)!=0 || $(FOR_WIN10)!=0
 LTLINKOPTS = $(LTLINKOPTS) /DYNAMICBASE /NODEFAULTLIB:kernel32.lib
 LTLINKOPTS = $(LTLINKOPTS) mincore.lib
 !IFDEF PSDKLIBPATH
 LTLINKOPTS = $(LTLINKOPTS) "/LIBPATH:$(PSDKLIBPATH)"
 !ENDIF
 !ENDIF
 
 !IF $(FOR_WIN10)!=0
-LTLINKOPTS = $(LTLINKOPTS) "/LIBPATH:$(UCRTLIBPATH)"
+LTLINKOPTS = $(LTLINKOPTS) /guard:cf "/LIBPATH:$(UCRTLIBPATH)"
 !IF $(DEBUG)>1
 LTLINKOPTS = $(LTLINKOPTS) /NODEFAULTLIB:libucrtd.lib /DEFAULTLIB:ucrtd.lib
 !ELSE
 LTLINKOPTS = $(LTLINKOPTS) /NODEFAULTLIB:libucrt.lib /DEFAULTLIB:ucrt.lib
 !ENDIF
@@ -1003,23 +1003,21 @@
 !ELSE
 LIBRESOBJS =
 !ENDIF
 
 # <<mark>>
-# All of the source code files.
+# Core source code files, part 1.
 #
-SRC1 = \
+SRC00 = \
   $(TOP)\src\alter.c \
   $(TOP)\src\analyze.c \
   $(TOP)\src\attach.c \
   $(TOP)\src\auth.c \
   $(TOP)\src\backup.c \
   $(TOP)\src\bitvec.c \
   $(TOP)\src\btmutex.c \
   $(TOP)\src\btree.c \
-  $(TOP)\src\btree.h \
-  $(TOP)\src\btreeInt.h \
   $(TOP)\src\build.c \
   $(TOP)\src\callback.c \
   $(TOP)\src\complete.c \
   $(TOP)\src\ctime.c \
   $(TOP)\src\date.c \
@@ -1029,12 +1027,10 @@
   $(TOP)\src\fault.c \
   $(TOP)\src\fkey.c \
   $(TOP)\src\func.c \
   $(TOP)\src\global.c \
   $(TOP)\src\hash.c \
-  $(TOP)\src\hash.h \
-  $(TOP)\src\hwtime.h \
   $(TOP)\src\insert.c \
   $(TOP)\src\journal.c \
   $(TOP)\src\legacy.c \
   $(TOP)\src\loadext.c \
   $(TOP)\src\main.c \
@@ -1043,45 +1039,33 @@
   $(TOP)\src\mem1.c \
   $(TOP)\src\mem2.c \
   $(TOP)\src\mem3.c \
   $(TOP)\src\mem5.c \
   $(TOP)\src\memjournal.c \
-  $(TOP)\src\msvc.h \
   $(TOP)\src\mutex.c \
-  $(TOP)\src\mutex.h \
   $(TOP)\src\mutex_noop.c \
   $(TOP)\src\mutex_unix.c \
   $(TOP)\src\mutex_w32.c \
   $(TOP)\src\notify.c \
   $(TOP)\src\os.c \
-  $(TOP)\src\os.h \
-  $(TOP)\src\os_common.h \
-  $(TOP)\src\os_setup.h \
   $(TOP)\src\os_unix.c \
-  $(TOP)\src\os_win.c \
-  $(TOP)\src\os_win.h
-SRC2 = \
+  $(TOP)\src\os_win.c
+
+# Core source code files, part 2.
+#
+SRC01 = \
   $(TOP)\src\pager.c \
-  $(TOP)\src\pager.h \
-  $(TOP)\src\parse.y \
   $(TOP)\src\pcache.c \
-  $(TOP)\src\pcache.h \
   $(TOP)\src\pcache1.c \
   $(TOP)\src\pragma.c \
-  $(TOP)\src\pragma.h \
   $(TOP)\src\prepare.c \
   $(TOP)\src\printf.c \
   $(TOP)\src\random.c \
   $(TOP)\src\resolve.c \
   $(TOP)\src\rowset.c \
   $(TOP)\src\select.c \
   $(TOP)\src\status.c \
-  $(TOP)\src\shell.c \
-  $(TOP)\src\sqlite.h.in \
-  $(TOP)\src\sqlite3ext.h \
-  $(TOP)\src\sqliteInt.h \
-  $(TOP)\src\sqliteLimit.h \
   $(TOP)\src\table.c \
   $(TOP)\src\threads.c \
   $(TOP)\src\tclsqlite.c \
   $(TOP)\src\tokenize.c \
   $(TOP)\src\treeview.c \
@@ -1089,87 +1073,136 @@
   $(TOP)\src\utf.c \
   $(TOP)\src\update.c \
   $(TOP)\src\util.c \
   $(TOP)\src\vacuum.c \
   $(TOP)\src\vdbe.c \
-  $(TOP)\src\vdbe.h \
   $(TOP)\src\vdbeapi.c \
   $(TOP)\src\vdbeaux.c \
   $(TOP)\src\vdbeblob.c \
   $(TOP)\src\vdbemem.c \
   $(TOP)\src\vdbesort.c \
   $(TOP)\src\vdbetrace.c \
-  $(TOP)\src\vdbeInt.h \
   $(TOP)\src\vtab.c \
-  $(TOP)\src\vxworks.h \
   $(TOP)\src\wal.c \
-  $(TOP)\src\wal.h \
   $(TOP)\src\walker.c \
   $(TOP)\src\where.c \
   $(TOP)\src\wherecode.c \
-  $(TOP)\src\whereexpr.c \
+  $(TOP)\src\whereexpr.c
+
+# Shell source code files.
+#
+SRC02 = \
+  $(TOP)\src\shell.c
+
+# Core miscellaneous files.
+#
+SRC03 = \
+  $(TOP)\src\parse.y
+
+# Core header files, part 1.
+#
+SRC04 = \
+  $(TOP)\src\btree.h \
+  $(TOP)\src\btreeInt.h \
+  $(TOP)\src\hash.h \
+  $(TOP)\src\hwtime.h \
+  $(TOP)\src\msvc.h \
+  $(TOP)\src\mutex.h \
+  $(TOP)\src\os.h \
+  $(TOP)\src\os_common.h \
+  $(TOP)\src\os_setup.h \
+  $(TOP)\src\os_win.h
+
+# Core header files, part 2.
+#
+SRC05 = \
+  $(TOP)\src\pager.h \
+  $(TOP)\src\pcache.h \
+  $(TOP)\src\pragma.h \
+  $(TOP)\src\sqlite.h.in \
+  $(TOP)\src\sqlite3ext.h \
+  $(TOP)\src\sqliteInt.h \
+  $(TOP)\src\sqliteLimit.h \
+  $(TOP)\src\vdbe.h \
+  $(TOP)\src\vdbeInt.h \
+  $(TOP)\src\vxworks.h \
+  $(TOP)\src\wal.h \
   $(TOP)\src\whereInt.h
 
-# Source code for extensions
+# Extension source code files, part 1.
 #
-SRC3 = \
+SRC06 = \
   $(TOP)\ext\fts1\fts1.c \
-  $(TOP)\ext\fts1\fts1.h \
   $(TOP)\ext\fts1\fts1_hash.c \
-  $(TOP)\ext\fts1\fts1_hash.h \
   $(TOP)\ext\fts1\fts1_porter.c \
-  $(TOP)\ext\fts1\fts1_tokenizer.h \
   $(TOP)\ext\fts1\fts1_tokenizer1.c \
   $(TOP)\ext\fts2\fts2.c \
-  $(TOP)\ext\fts2\fts2.h \
   $(TOP)\ext\fts2\fts2_hash.c \
-  $(TOP)\ext\fts2\fts2_hash.h \
   $(TOP)\ext\fts2\fts2_icu.c \
   $(TOP)\ext\fts2\fts2_porter.c \
-  $(TOP)\ext\fts2\fts2_tokenizer.h \
   $(TOP)\ext\fts2\fts2_tokenizer.c \
   $(TOP)\ext\fts2\fts2_tokenizer1.c
-SRC4 = \
+
+# Extension source code files, part 2.
+#
+SRC07 = \
   $(TOP)\ext\fts3\fts3.c \
-  $(TOP)\ext\fts3\fts3.h \
-  $(TOP)\ext\fts3\fts3Int.h \
   $(TOP)\ext\fts3\fts3_aux.c \
   $(TOP)\ext\fts3\fts3_expr.c \
   $(TOP)\ext\fts3\fts3_hash.c \
-  $(TOP)\ext\fts3\fts3_hash.h \
   $(TOP)\ext\fts3\fts3_icu.c \
   $(TOP)\ext\fts3\fts3_porter.c \
   $(TOP)\ext\fts3\fts3_snippet.c \
-  $(TOP)\ext\fts3\fts3_tokenizer.h \
   $(TOP)\ext\fts3\fts3_tokenizer.c \
   $(TOP)\ext\fts3\fts3_tokenizer1.c \
   $(TOP)\ext\fts3\fts3_tokenize_vtab.c \
   $(TOP)\ext\fts3\fts3_unicode.c \
   $(TOP)\ext\fts3\fts3_unicode2.c \
   $(TOP)\ext\fts3\fts3_write.c \
-  $(TOP)\ext\icu\sqliteicu.h \
   $(TOP)\ext\icu\icu.c \
-  $(TOP)\ext\rtree\rtree.h \
   $(TOP)\ext\rtree\rtree.c \
-  $(TOP)\ext\rbu\sqlite3rbu.h \
   $(TOP)\ext\rbu\sqlite3rbu.c \
   $(TOP)\ext\misc\json1.c
 
+# Extension header files, part 1.
+#
+SRC08 = \
+  $(TOP)\ext\fts1\fts1.h \
+  $(TOP)\ext\fts1\fts1_hash.h \
+  $(TOP)\ext\fts1\fts1_tokenizer.h \
+  $(TOP)\ext\fts2\fts2.h \
+  $(TOP)\ext\fts2\fts2_hash.h \
+  $(TOP)\ext\fts2\fts2_tokenizer.h
+
+# Extension header files, part 2.
+#
+SRC09 = \
+  $(TOP)\ext\fts3\fts3.h \
+  $(TOP)\ext\fts3\fts3Int.h \
+  $(TOP)\ext\fts3\fts3_hash.h \
+  $(TOP)\ext\fts3\fts3_tokenizer.h \
+  $(TOP)\ext\icu\sqliteicu.h \
+  $(TOP)\ext\rtree\rtree.h \
+  $(TOP)\ext\rbu\sqlite3rbu.h
 
 # Generated source code files
 #
-SRC5 = \
-  keywordhash.h \
+SRC10 = \
   opcodes.c \
+  parse.c
+
+# Generated header files
+#
+SRC11 = \
+  keywordhash.h \
   opcodes.h \
-  parse.c \
   parse.h \
   $(SQLITE3H)
 
 # All source code files.
 #
-SRC = $(SRC1) $(SRC2) $(SRC3) $(SRC4) $(SRC5)
+SRC = $(SRC00) $(SRC01) $(SRC02) $(SRC03) $(SRC04) $(SRC05) $(SRC06) $(SRC07) $(SRC08) $(SRC09) $(SRC10) $(SRC11)
 
 # Source code to the test files.
 #
 TESTSRC = \
   $(TOP)\src\test1.c \
@@ -1214,11 +1247,11 @@
   $(TOP)\src\test_wsd.c \
   $(TOP)\ext\fts3\fts3_term.c \
   $(TOP)\ext\fts3\fts3_test.c \
   $(TOP)\ext\rbu\test_rbu.c
 
-# Statically linked extensions
+# Statically linked extensions.
 #
 TESTEXT = \
   $(TOP)\ext\misc\amatch.c \
   $(TOP)\ext\misc\closure.c \
   $(TOP)\ext\misc\eval.c \
@@ -1234,60 +1267,18 @@
   $(TOP)\ext\misc\series.c \
   $(TOP)\ext\misc\spellfix.c \
   $(TOP)\ext\misc\totype.c \
   $(TOP)\ext\misc\wholenumber.c
 
-
 # Source code to the library files needed by the test fixture
 #
 TESTSRC2 = \
-  $(TOP)\src\attach.c \
-  $(TOP)\src\backup.c \
-  $(TOP)\src\bitvec.c \
-  $(TOP)\src\btree.c \
-  $(TOP)\src\build.c \
-  $(TOP)\src\ctime.c \
-  $(TOP)\src\date.c \
-  $(TOP)\src\dbstat.c \
-  $(TOP)\src\expr.c \
-  $(TOP)\src\func.c \
-  $(TOP)\src\insert.c \
-  $(TOP)\src\wal.c \
-  $(TOP)\src\main.c \
-  $(TOP)\src\mem5.c \
-  $(TOP)\src\os.c \
-  $(TOP)\src\os_unix.c \
-  $(TOP)\src\os_win.c \
-  $(TOP)\src\pager.c \
-  $(TOP)\src\pragma.c \
-  $(TOP)\src\prepare.c \
-  $(TOP)\src\printf.c \
-  $(TOP)\src\random.c \
-  $(TOP)\src\pcache.c \
-  $(TOP)\src\pcache1.c \
-  $(TOP)\src\select.c \
-  $(TOP)\src\tokenize.c \
-  $(TOP)\src\utf.c \
-  $(TOP)\src\util.c \
-  $(TOP)\src\vdbeapi.c \
-  $(TOP)\src\vdbeaux.c \
-  $(TOP)\src\vdbe.c \
-  $(TOP)\src\vdbemem.c \
-  $(TOP)\src\vdbesort.c \
-  $(TOP)\src\vdbetrace.c \
-  $(TOP)\src\where.c \
-  $(TOP)\src\wherecode.c \
-  $(TOP)\src\whereexpr.c \
-  parse.c \
-  $(TOP)\ext\fts3\fts3.c \
-  $(TOP)\ext\fts3\fts3_aux.c \
-  $(TOP)\ext\fts3\fts3_expr.c \
-  $(TOP)\ext\fts3\fts3_tokenizer.c \
-  $(TOP)\ext\fts3\fts3_tokenize_vtab.c \
-  $(TOP)\ext\fts3\fts3_unicode.c \
-  $(TOP)\ext\fts3\fts3_unicode2.c \
-  $(TOP)\ext\fts3\fts3_write.c \
+  $(SRC00) \
+  $(SRC01) \
+  $(SRC06) \
+  $(SRC07) \
+  $(SRC10) \
   $(TOP)\ext\async\sqlite3async.c
 
 # Header files used by all library source files.
 #
 HDR = \
@@ -1357,11 +1348,11 @@
 
 # Additional compiler options for the shell.  These are only effective
 # when the shell is not being dynamically linked.
 #
 !IF $(DYNAMIC_SHELL)==0 && $(FOR_WIN10)==0
-SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_SHELL_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_FTS5
+SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_SHELL_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_EXPLAIN_COMMENTS
 !ENDIF
 
 # <<mark>>
 # Extra compiler options for various test tools.
 #
@@ -1458,15 +1449,22 @@
 # all that automatic generation.
 #
 .target_source:	$(SRC) $(TOP)\tool\vdbe-compress.tcl fts5.c
 	-rmdir /Q/S tsrc 2>NUL
 	-mkdir tsrc
-	for %i in ($(SRC1)) do copy /Y %i tsrc
-	for %i in ($(SRC2)) do copy /Y %i tsrc
-	for %i in ($(SRC3)) do copy /Y %i tsrc
-	for %i in ($(SRC4)) do copy /Y %i tsrc
-	for %i in ($(SRC5)) do copy /Y %i tsrc
+	for %i in ($(SRC00)) do copy /Y %i tsrc
+	for %i in ($(SRC01)) do copy /Y %i tsrc
+	for %i in ($(SRC02)) do copy /Y %i tsrc
+	for %i in ($(SRC03)) do copy /Y %i tsrc
+	for %i in ($(SRC04)) do copy /Y %i tsrc
+	for %i in ($(SRC05)) do copy /Y %i tsrc
+	for %i in ($(SRC06)) do copy /Y %i tsrc
+	for %i in ($(SRC07)) do copy /Y %i tsrc
+	for %i in ($(SRC08)) do copy /Y %i tsrc
+	for %i in ($(SRC09)) do copy /Y %i tsrc
+	for %i in ($(SRC10)) do copy /Y %i tsrc
+	for %i in ($(SRC11)) do copy /Y %i tsrc
 	copy /Y fts5.c tsrc
 	copy /Y fts5.h tsrc
 	del /Q tsrc\sqlite.h.in tsrc\parse.y 2>NUL
 	$(TCLSH_CMD) $(TOP)\tool\vdbe-compress.tcl $(OPTS) < tsrc\vdbe.c > vdbe.new
 	move vdbe.new tsrc\vdbe.c
@@ -1907,11 +1905,11 @@
 #
 TESTFIXTURE_FLAGS = -DTCLSH=1 -DSQLITE_TEST=1 -DSQLITE_CRASH_TEST=1
 TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_SERVER=1 -DSQLITE_PRIVATE=""
 TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_CORE $(NO_WARN)
 
-TESTFIXTURE_SRC0 = $(TESTEXT) $(TESTSRC2) $(SHELL_CORE_DEP)
+TESTFIXTURE_SRC0 = $(TESTEXT) $(TESTSRC2)
 TESTFIXTURE_SRC1 = $(TESTEXT) $(SQLITE3C)
 !IF $(USE_AMALGAMATION)==0
 TESTFIXTURE_SRC = $(TESTSRC) $(TOP)\src\tclsqlite.c $(TESTFIXTURE_SRC0)
 !ELSE
 TESTFIXTURE_SRC = $(TESTSRC) $(TOP)\src\tclsqlite.c $(TESTFIXTURE_SRC1)

Index: autoconf/Makefile.am
==================================================================
--- autoconf/Makefile.am
+++ autoconf/Makefile.am
@@ -4,15 +4,14 @@
 lib_LTLIBRARIES = libsqlite3.la
 libsqlite3_la_SOURCES = sqlite3.c
 libsqlite3_la_LDFLAGS = -no-undefined -version-info 8:6:8
 
 bin_PROGRAMS = sqlite3
-sqlite3_SOURCES = shell.c sqlite3.h
-EXTRA_sqlite3_SOURCES = sqlite3.c
-sqlite3_LDADD = @EXTRA_SHELL_OBJ@ @READLINE_LIBS@
+sqlite3_SOURCES = shell.c sqlite3.c sqlite3.h
+sqlite3_LDADD = @READLINE_LIBS@
 sqlite3_DEPENDENCIES = @EXTRA_SHELL_OBJ@
-sqlite3_CFLAGS = $(AM_CFLAGS)
+sqlite3_CFLAGS = $(AM_CFLAGS) -DSQLITE_ENABLE_EXPLAIN_COMMENTS
 
 include_HEADERS = sqlite3.h sqlite3ext.h
 
 EXTRA_DIST = sqlite3.1 tea Makefile.msc sqlite3.rc README.txt
 pkgconfigdir = ${libdir}/pkgconfig

Index: autoconf/Makefile.msc
==================================================================
--- autoconf/Makefile.msc
+++ autoconf/Makefile.msc
@@ -117,16 +117,16 @@
 #
 !IFNDEF FOR_WINRT
 FOR_WINRT = 0
 !ENDIF
 
-# Set this non-0 to compile binaries suitable for the UAP environment.
+# Set this non-0 to compile binaries suitable for the UWP environment.
 # This setting does not apply to any binaries that require Tcl to operate
 # properly (i.e. the text fixture, etc).
 #
-!IFNDEF FOR_UAP
-FOR_UAP = 0
+!IFNDEF FOR_UWP
+FOR_UWP = 0
 !ENDIF
 
 # Set this non-0 to compile binaries suitable for the Windows 10 platform.
 #
 !IFNDEF FOR_WIN10
@@ -397,12 +397,12 @@
 TCC = $(CC) -nologo -W4 -DINCLUDE_MSVC_H=1 $(CCOPTS) $(TCCOPTS)
 !ELSE
 TCC = $(CC) -nologo -W3 $(CCOPTS) $(TCCOPTS)
 !ENDIF
 
-TCC = $(TCC) -DSQLITE_OS_WIN=1 -I$(TOP) -fp:precise
-RCC = $(RC) -DSQLITE_OS_WIN=1 -I$(TOP) $(RCOPTS) $(RCCOPTS)
+TCC = $(TCC) -DSQLITE_OS_WIN=1 -I. -I$(TOP) -fp:precise
+RCC = $(RC) -DSQLITE_OS_WIN=1 -I. -I$(TOP) $(RCOPTS) $(RCCOPTS)
 
 # Adjust the names of the primary targets for use with Windows 10.
 #
 !IF $(FOR_WIN10)!=0
 SQLITE3DLL = winsqlite3.dll
@@ -534,12 +534,12 @@
 !ENDIF
 
 # C compiler options for the Windows 10 platform (needs MSVC 2015).
 #
 !IF $(FOR_WIN10)!=0
-TCC = $(TCC) /guard:cf -D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE
-BCC = $(BCC) /guard:cf -D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE
+TCC = $(TCC) /d2guard4 -D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE
+BCC = $(BCC) /d2guard4 -D_ARM_WINAPI_PARTITION_DESKTOP_SDK_AVAILABLE
 !ENDIF
 
 # Also, we need to dynamically link to the correct MSVC runtime
 # when compiling for WinRT (e.g. debug or release) OR if the
 # USE_CRT_DLL option is set to force dynamically linking to the
@@ -800,23 +800,23 @@
 LTLINKOPTS = $(LTLINKOPTS) /DYNAMICBASE
 LTLINKOPTS = $(LTLINKOPTS) WindowsPhoneCore.lib RuntimeObject.lib PhoneAppModelHost.lib
 LTLINKOPTS = $(LTLINKOPTS) /NODEFAULTLIB:kernel32.lib /NODEFAULTLIB:ole32.lib
 !ENDIF
 
-# When compiling for UAP or the Windows 10 platform, some extra linker
+# When compiling for UWP or the Windows 10 platform, some extra linker
 # options are also required.
 #
-!IF $(FOR_UAP)!=0 || $(FOR_WIN10)!=0
+!IF $(FOR_UWP)!=0 || $(FOR_WIN10)!=0
 LTLINKOPTS = $(LTLINKOPTS) /DYNAMICBASE /NODEFAULTLIB:kernel32.lib
 LTLINKOPTS = $(LTLINKOPTS) mincore.lib
 !IFDEF PSDKLIBPATH
 LTLINKOPTS = $(LTLINKOPTS) "/LIBPATH:$(PSDKLIBPATH)"
 !ENDIF
 !ENDIF
 
 !IF $(FOR_WIN10)!=0
-LTLINKOPTS = $(LTLINKOPTS) "/LIBPATH:$(UCRTLIBPATH)"
+LTLINKOPTS = $(LTLINKOPTS) /guard:cf "/LIBPATH:$(UCRTLIBPATH)"
 !IF $(DEBUG)>1
 LTLINKOPTS = $(LTLINKOPTS) /NODEFAULTLIB:libucrtd.lib /DEFAULTLIB:ucrtd.lib
 !ELSE
 LTLINKOPTS = $(LTLINKOPTS) /NODEFAULTLIB:libucrt.lib /DEFAULTLIB:ucrt.lib
 !ENDIF
@@ -854,11 +854,11 @@
 
 # Additional compiler options for the shell.  These are only effective
 # when the shell is not being dynamically linked.
 #
 !IF $(DYNAMIC_SHELL)==0 && $(FOR_WIN10)==0
-SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_SHELL_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_FTS5
+SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_SHELL_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_EXPLAIN_COMMENTS
 !ENDIF
 
 
 # This is the default Makefile target.  The objects listed here
 # are what get build when you type just "make" with no arguments.

Index: autoconf/README.txt
==================================================================
--- autoconf/README.txt
+++ autoconf/README.txt
@@ -1,15 +1,15 @@
 This package contains:
 
- * the SQLite library amalgamation (single file) source code distribution,
- * the shell.c file used to build the sqlite3 shell too, and
- * the sqlite3.h and sqlite3ext.h header files required to link programs
-   and sqlite extensions against the installed libary.
+ * the SQLite library amalgamation source code file: sqlite3.c
+ * the sqlite3.h and sqlite3ext.h header files that define the C-language
+   interface to the sqlite3.c library file
+ * the shell.c file used to build the sqlite3 command-line shell program
  * autoconf/automake installation infrastucture for building on POSIX
-   compliant systems.
+   compliant systems
  * a Makefile.msc and sqlite3.rc for building with Microsoft Visual C++ on
-   Windows.
+   Windows
 
 SUMMARY OF HOW TO BUILD
 =======================
 
   Unix:      ./configure; make
@@ -37,11 +37,11 @@
 to produce a smaller installation footprint.
 
 Other SQLite compilation parameters can also be set using CFLAGS. For
 example:
 
-  $ CFLAGS="-Os -DSQLITE_OMIT_TRIGGERS" ./configure
+  $ CFLAGS="-Os -DSQLITE_THREADSAFE=0" ./configure
 
 
 BUILDING WITH MICROSOFT VISUAL C++
 ==================================
 
@@ -73,14 +73,14 @@
 above, something like the following macro will need to be added to the
 NMAKE command line as well:
 
   "NSDKLIBPATH=%WindowsSdkDir%\..\8.1\lib\winv6.3\um\x86"
 
-Building for UAP 10.0
+Building for UWP 10.0
 ---------------------
 
-  FOR_WINRT=1 FOR_UAP=1
+  FOR_WINRT=1 FOR_UWP=1
 
 Using Microsoft Visual C++ 2015 (or later) is required.  When using the
 above, something like the following macros will need to be added to the
 NMAKE command line as well:
 

Index: ext/fts3/fts3Int.h
==================================================================
--- ext/fts3/fts3Int.h
+++ ext/fts3/fts3Int.h
@@ -15,10 +15,16 @@
 #define _FTSINT_H
 
 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG) 
 # define NDEBUG 1
 #endif
+
+/* FTS3/FTS4 require virtual tables */
+#ifdef SQLITE_OMIT_VIRTUALTABLE
+# undef SQLITE_ENABLE_FTS3
+# undef SQLITE_ENABLE_FTS4
+#endif
 
 /*
 ** FTS4 is really an extension for FTS3.  It is enabled using the
 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also all
 ** the SQLITE_ENABLE_FTS4 macro to serve as an alisse for SQLITE_ENABLE_FTS3.

Index: ext/fts3/unicode/mkunicode.tcl
==================================================================
--- ext/fts3/unicode/mkunicode.tcl
+++ ext/fts3/unicode/mkunicode.tcl
@@ -224,13 +224,13 @@
   puts "*/"
   puts "int ${zFunc}\(int c)\{"
   an_print_range_array $lRange
   an_print_ascii_bitmap $lRange
   puts {
-  if( c<128 ){
+  if( (unsigned int)c<128 ){
     return ( (aAscii[c >> 5] & (1 << (c & 0x001F)))==0 );
-  }else if( c<(1<<22) ){
+  }else if( (unsigned int)c<(1<<22) ){
     unsigned int key = (((unsigned int)c)<<10) | 0x000003FF;
     int iRes = 0;
     int iHi = sizeof(aEntry)/sizeof(aEntry[0]) - 1;
     int iLo = 0;
     while( iHi>=iLo ){

Index: ext/fts5/fts5Int.h
==================================================================
--- ext/fts5/fts5Int.h
+++ ext/fts5/fts5Int.h
@@ -24,10 +24,11 @@
 #ifndef SQLITE_AMALGAMATION
 
 typedef unsigned char  u8;
 typedef unsigned int   u32;
 typedef unsigned short u16;
+typedef short i16;
 typedef sqlite3_int64 i64;
 typedef sqlite3_uint64 u64;
 
 #define ArraySize(x) ((int)(sizeof(x) / sizeof(x[0])))
 
@@ -77,10 +78,20 @@
 extern int sqlite3_fts5_may_be_corrupt;
 # define assert_nc(x) assert(sqlite3_fts5_may_be_corrupt || (x))
 #else
 # define assert_nc(x) assert(x)
 #endif
+
+/* Mark a function parameter as unused, to suppress nuisance compiler
+** warnings. */
+#ifndef UNUSED_PARAM
+# define UNUSED_PARAM(X)  (void)(X)
+#endif
+
+#ifndef UNUSED_PARAM2
+# define UNUSED_PARAM2(X, Y)  (void)(X), (void)(Y)
+#endif
 
 typedef struct Fts5Global Fts5Global;
 typedef struct Fts5Colset Fts5Colset;
 
 /* If a NEAR() clump or phrase may only match a specific set of columns, 
@@ -343,20 +354,10 @@
 ** Create/destroy an Fts5Index object.
 */
 int sqlite3Fts5IndexOpen(Fts5Config *pConfig, int bCreate, Fts5Index**, char**);
 int sqlite3Fts5IndexClose(Fts5Index *p);
 
-/*
-** for(
-**   sqlite3Fts5IndexQuery(p, "token", 5, 0, 0, &pIter);
-**   0==sqlite3Fts5IterEof(pIter);
-**   sqlite3Fts5IterNext(pIter)
-** ){
-**   i64 iRowid = sqlite3Fts5IterRowid(pIter);
-** }
-*/
-
 /*
 ** Return a simple checksum value based on the arguments.
 */
 u64 sqlite3Fts5IndexEntryCksum(
   i64 iRowid, 
@@ -394,11 +395,10 @@
 ** The various operations on open token or token prefix iterators opened
 ** using sqlite3Fts5IndexQuery().
 */
 int sqlite3Fts5IterNext(Fts5IndexIter*);
 int sqlite3Fts5IterNextFrom(Fts5IndexIter*, i64 iMatch);
-i64 sqlite3Fts5IterRowid(Fts5IndexIter*);
 
 /*
 ** Close an iterator opened by sqlite3Fts5IndexQuery().
 */
 void sqlite3Fts5IterClose(Fts5IndexIter*);
@@ -679,11 +679,11 @@
     Fts5Config*, Fts5Expr*, Fts5PoslistPopulator*, int, const char*, int
 );
 void sqlite3Fts5ExprCheckPoslists(Fts5Expr*, i64);
 void sqlite3Fts5ExprClearEof(Fts5Expr*);
 
-int sqlite3Fts5ExprClonePhrase(Fts5Config*, Fts5Expr*, int, Fts5Expr**);
+int sqlite3Fts5ExprClonePhrase(Fts5Expr*, int, Fts5Expr**);
 
 int sqlite3Fts5ExprPhraseCollist(Fts5Expr *, int, const u8 **, int *);
 
 /*******************************************
 ** The fts5_expr.c API above this point is used by the other hand-written

Index: ext/fts5/fts5_aux.c
==================================================================
--- ext/fts5/fts5_aux.c
+++ ext/fts5/fts5_aux.c
@@ -155,10 +155,12 @@
   int iEndOff                     /* End offset of token */
 ){
   HighlightContext *p = (HighlightContext*)pContext;
   int rc = SQLITE_OK;
   int iPos;
+
+  UNUSED_PARAM2(pToken, nToken);
 
   if( tflags & FTS5_TOKEN_COLOCATED ) return SQLITE_OK;
   iPos = p->iPos++;
 
   if( p->iRangeEnd>0 ){
@@ -389,10 +391,11 @@
   const Fts5ExtensionApi *pApi, 
   Fts5Context *pFts,
   void *pUserData                 /* Pointer to sqlite3_int64 variable */
 ){
   sqlite3_int64 *pn = (sqlite3_int64*)pUserData;
+  UNUSED_PARAM2(pApi, pFts);
   (*pn)++;
   return SQLITE_OK;
 }
 
 /*

Index: ext/fts5/fts5_buffer.c
==================================================================
--- ext/fts5/fts5_buffer.c
+++ ext/fts5/fts5_buffer.c
@@ -234,11 +234,11 @@
 int sqlite3Fts5PoslistWriterAppend(
   Fts5Buffer *pBuf, 
   Fts5PoslistWriter *pWriter,
   i64 iPos
 ){
-  int rc;
+  int rc = 0;   /* Initialized only to suppress erroneous warning from Clang */
   if( fts5BufferGrow(&rc, pBuf, 5+5+5) ) return rc;
   sqlite3Fts5PoslistSafeAppend(pBuf, &pWriter->iPrev, iPos);
   return SQLITE_OK;
 }
 
@@ -388,8 +388,5 @@
       }
     }
     sqlite3_free(p);
   }
 }
-
-
-

Index: ext/fts5/fts5_config.c
==================================================================
--- ext/fts5/fts5_config.c
+++ ext/fts5/fts5_config.c
@@ -204,11 +204,11 @@
 static int fts5ConfigSetEnum(
   const Fts5Enum *aEnum, 
   const char *zEnum, 
   int *peVal
 ){
-  int nEnum = strlen(zEnum);
+  int nEnum = (int)strlen(zEnum);
   int i;
   int iVal = -1;
 
   for(i=0; aEnum[i].zName; i++){
     if( sqlite3_strnicmp(aEnum[i].zName, zEnum, nEnum)==0 ){
@@ -941,6 +941,5 @@
   if( rc==SQLITE_OK ){
     pConfig->iCookie = iCookie;
   }
   return rc;
 }
-

Index: ext/fts5/fts5_expr.c
==================================================================
--- ext/fts5/fts5_expr.c
+++ ext/fts5/fts5_expr.c
@@ -318,12 +318,10 @@
 /*
 ** Argument pTerm must be a synonym iterator.
 */
 static int fts5ExprSynonymList(
   Fts5ExprTerm *pTerm, 
-  int bCollist, 
-  Fts5Colset *pColset,
   i64 iRowid,
   Fts5Buffer *pBuf,               /* Use this buffer for space if required */
   u8 **pa, int *pn
 ){
   Fts5PoslistReader aStatic[4];
@@ -403,11 +401,10 @@
 ** otherwise. It is not considered an error code if the current rowid is 
 ** not a match.
 */
 static int fts5ExprPhraseIsMatch(
   Fts5ExprNode *pNode,            /* Node pPhrase belongs to */
-  Fts5Colset *pColset,            /* Restrict matches to these columns */
   Fts5ExprPhrase *pPhrase,        /* Phrase object to initialize */
   int *pbMatch                    /* OUT: Set to true if really a match */
 ){
   Fts5PoslistWriter writer = {0};
   Fts5PoslistReader aStatic[4];
@@ -432,13 +429,11 @@
     int n = 0;
     int bFlag = 0;
     u8 *a = 0;
     if( pTerm->pSynonym ){
       Fts5Buffer buf = {0, 0, 0};
-      rc = fts5ExprSynonymList(
-          pTerm, 0, pColset, pNode->iRowid, &buf, &a, &n
-      );
+      rc = fts5ExprSynonymList(pTerm, pNode->iRowid, &buf, &a, &n);
       if( rc ){
         sqlite3_free(a);
         goto ismatch_out;
       }
       if( a==buf.p ) bFlag = 1;
@@ -725,11 +720,11 @@
     ** phrase is not a match, break out of the loop early.  */
     for(i=0; rc==SQLITE_OK && i<pNear->nPhrase; i++){
       Fts5ExprPhrase *pPhrase = pNear->apPhrase[i];
       if( pPhrase->nTerm>1 || pPhrase->aTerm[0].pSynonym || pNear->pColset ){
         int bMatch = 0;
-        rc = fts5ExprPhraseIsMatch(pNode, pNear->pColset, pPhrase, &bMatch);
+        rc = fts5ExprPhraseIsMatch(pNode, pPhrase, &bMatch);
         if( bMatch==0 ) break;
       }else{
         Fts5IndexIter *pIter = pPhrase->aTerm[0].pIter;
         fts5BufferSet(&rc, &pPhrase->poslist, pIter->nData, pIter->pData);
       }
@@ -1473,10 +1468,12 @@
 ){
   int rc = SQLITE_OK;
   const int SZALLOC = 8;
   TokenCtx *pCtx = (TokenCtx*)pContext;
   Fts5ExprPhrase *pPhrase = pCtx->pPhrase;
+
+  UNUSED_PARAM2(iUnused1, iUnused2);
 
   /* If an error has already occurred, this is a no-op */
   if( pCtx->rc!=SQLITE_OK ) return pCtx->rc;
 
   assert( pPhrase==0 || pPhrase->nTerm>0 );
@@ -1609,26 +1606,21 @@
 /*
 ** Create a new FTS5 expression by cloning phrase iPhrase of the
 ** expression passed as the second argument.
 */
 int sqlite3Fts5ExprClonePhrase(
-  Fts5Config *pConfig,
   Fts5Expr *pExpr, 
   int iPhrase, 
   Fts5Expr **ppNew
 ){
   int rc = SQLITE_OK;             /* Return code */
   Fts5ExprPhrase *pOrig;          /* The phrase extracted from pExpr */
   int i;                          /* Used to iterate through phrase terms */
-
   Fts5Expr *pNew = 0;             /* Expression to return via *ppNew */
-
   TokenCtx sCtx = {0,0};          /* Context object for fts5ParseTokenize */
 
-
   pOrig = pExpr->apExprPhrase[iPhrase];
-
   pNew = (Fts5Expr*)sqlite3Fts5MallocZero(&rc, sizeof(Fts5Expr));
   if( rc==SQLITE_OK ){
     pNew->apExprPhrase = (Fts5ExprPhrase**)sqlite3Fts5MallocZero(&rc, 
         sizeof(Fts5ExprPhrase*));
   }
@@ -2397,16 +2389,18 @@
 static int fts5ExprPopulatePoslistsCb(
   void *pCtx,                /* Copy of 2nd argument to xTokenize() */
   int tflags,                /* Mask of FTS5_TOKEN_* flags */
   const char *pToken,        /* Pointer to buffer containing token */
   int nToken,                /* Size of token in bytes */
-  int iStart,                /* Byte offset of token within input text */
-  int iEnd                   /* Byte offset of end of token within input text */
+  int iUnused1,              /* Byte offset of token within input text */
+  int iUnused2               /* Byte offset of end of token within input text */
 ){
   Fts5ExprCtx *p = (Fts5ExprCtx*)pCtx;
   Fts5Expr *pExpr = p->pExpr;
   int i;
+
+  UNUSED_PARAM2(iUnused1, iUnused2);
 
   if( (tflags & FTS5_TOKEN_COLOCATED)==0 ) p->iOff++;
   for(i=0; i<pExpr->nPhrase; i++){
     Fts5ExprTerm *pTerm;
     if( p->aPopulator[i].bOk==0 ) continue;
@@ -2548,11 +2542,11 @@
   ){
     Fts5ExprTerm *pTerm = &pPhrase->aTerm[0];
     if( pTerm->pSynonym ){
       Fts5Buffer *pBuf = (Fts5Buffer*)&pTerm->pSynonym[1];
       rc = fts5ExprSynonymList(
-          pTerm, 1, 0, pNode->iRowid, pBuf, (u8**)ppCollist, pnCollist
+          pTerm, pNode->iRowid, pBuf, (u8**)ppCollist, pnCollist
       );
     }else{
       *ppCollist = pPhrase->aTerm[0].pIter->pData;
       *pnCollist = pPhrase->aTerm[0].pIter->nData;
     }

Index: ext/fts5/fts5_hash.c
==================================================================
--- ext/fts5/fts5_hash.c
+++ ext/fts5/fts5_hash.c
@@ -60,14 +60,14 @@
   Fts5HashEntry *pScanNext;       /* Next entry in sorted order */
   
   int nAlloc;                     /* Total size of allocation */
   int iSzPoslist;                 /* Offset of space for 4-byte poslist size */
   int nData;                      /* Total bytes of data (incl. structure) */
+  int nKey;                       /* Length of zKey[] in bytes */
   u8 bDel;                        /* Set delete-flag @ iSzPoslist */
   u8 bContent;                    /* Set content-flag (detail=none mode) */
-
-  int iCol;                       /* Column of last value written */
+  i16 iCol;                       /* Column of last value written */
   int iPos;                       /* Position of last value written */
   i64 iRowid;                     /* Rowid of last value written */
   char zKey[8];                   /* Nul-terminated entry key */
 };
 
@@ -243,12 +243,12 @@
 
   /* Attempt to locate an existing hash entry */
   iHash = fts5HashKey2(pHash->nSlot, (u8)bByte, (const u8*)pToken, nToken);
   for(p=pHash->aSlot[iHash]; p; p=p->pHashNext){
     if( p->zKey[0]==bByte 
+     && p->nKey==nToken
      && memcmp(&p->zKey[1], pToken, nToken)==0 
-     && p->zKey[nToken+1]==0 
     ){
       break;
     }
   }
 
@@ -271,10 +271,11 @@
     memset(p, 0, FTS5_HASHENTRYSIZE);
     p->nAlloc = nByte;
     p->zKey[0] = bByte;
     memcpy(&p->zKey[1], pToken, nToken);
     assert( iHash==fts5HashKey(pHash->nSlot, (u8*)p->zKey, nToken+1) );
+    p->nKey = nToken;
     p->zKey[nToken+1] = '\0';
     p->nData = nToken+1 + 1 + FTS5_HASHENTRYSIZE;
     p->pHashNext = pHash->aSlot[iHash];
     pHash->aSlot[iHash] = p;
     pHash->nEntry++;

Index: ext/fts5/fts5_index.c
==================================================================
--- ext/fts5/fts5_index.c
+++ ext/fts5/fts5_index.c
@@ -605,21 +605,10 @@
   int nCmp = MIN(pLeft->n, pRight->n);
   int res = memcmp(pLeft->p, pRight->p, nCmp);
   return (res==0 ? (pLeft->n - pRight->n) : res);
 }
 
-#ifdef SQLITE_DEBUG
-static int fts5BlobCompare(
-  const u8 *pLeft, int nLeft, 
-  const u8 *pRight, int nRight
-){
-  int nCmp = MIN(nLeft, nRight);
-  int res = memcmp(pLeft, pRight, nCmp);
-  return (res==0 ? (nLeft - nRight) : res);
-}
-#endif
-
 static int fts5LeafFirstTermOff(Fts5Data *pLeaf){
   int ret;
   fts5GetVarint32(&pLeaf->p[pLeaf->szLeaf], ret);
   return ret;
 }
@@ -877,28 +866,37 @@
     for(iLvl=0; rc==SQLITE_OK && iLvl<nLevel; iLvl++){
       Fts5StructureLevel *pLvl = &pRet->aLevel[iLvl];
       int nTotal;
       int iSeg;
 
-      i += fts5GetVarint32(&pData[i], pLvl->nMerge);
-      i += fts5GetVarint32(&pData[i], nTotal);
-      assert( nTotal>=pLvl->nMerge );
-      pLvl->aSeg = (Fts5StructureSegment*)sqlite3Fts5MallocZero(&rc, 
-          nTotal * sizeof(Fts5StructureSegment)
-      );
+      if( i>=nData ){
+        rc = FTS5_CORRUPT;
+      }else{
+        i += fts5GetVarint32(&pData[i], pLvl->nMerge);
+        i += fts5GetVarint32(&pData[i], nTotal);
+        assert( nTotal>=pLvl->nMerge );
+        pLvl->aSeg = (Fts5StructureSegment*)sqlite3Fts5MallocZero(&rc, 
+            nTotal * sizeof(Fts5StructureSegment)
+        );
+      }
 
       if( rc==SQLITE_OK ){
         pLvl->nSeg = nTotal;
         for(iSeg=0; iSeg<nTotal; iSeg++){
+          if( i>=nData ){
+            rc = FTS5_CORRUPT;
+            break;
+          }
           i += fts5GetVarint32(&pData[i], pLvl->aSeg[iSeg].iSegid);
           i += fts5GetVarint32(&pData[i], pLvl->aSeg[iSeg].pgnoFirst);
           i += fts5GetVarint32(&pData[i], pLvl->aSeg[iSeg].pgnoLast);
         }
-      }else{
-        fts5StructureRelease(pRet);
-        pRet = 0;
       }
+    }
+    if( rc!=SQLITE_OK ){
+      fts5StructureRelease(pRet);
+      pRet = 0;
     }
   }
 
   *ppOut = pRet;
   return rc;
@@ -1562,10 +1560,14 @@
   u8 *a = pIter->pLeaf->p;        /* Buffer to read data from */
   int iOff = pIter->iLeafOffset;  /* Offset to read at */
   int nNew;                       /* Bytes of new data */
 
   iOff += fts5GetVarint32(&a[iOff], nNew);
+  if( iOff+nNew>pIter->pLeaf->nn ){
+    p->rc = FTS5_CORRUPT;
+    return;
+  }
   pIter->term.n = nKeep;
   fts5BufferAppendBlob(&p->rc, &pIter->term, nNew, &a[iOff]);
   iOff += nNew;
   pIter->iTermLeafOffset = iOff;
   pIter->iTermLeafPgno = pIter->iLeafPgno;
@@ -1768,14 +1770,16 @@
 ** This version of fts5SegIterNext() is only used by reverse iterators.
 */
 static void fts5SegIterNext_Reverse(
   Fts5Index *p,                   /* FTS5 backend object */
   Fts5SegIter *pIter,             /* Iterator to advance */
-  int *pbNewTerm                  /* OUT: Set for new term */
+  int *pbUnused                   /* Unused */
 ){
   assert( pIter->flags & FTS5_SEGITER_REVERSE );
   assert( pIter->pNextLeaf==0 );
+  UNUSED_PARAM(pbUnused);
+
   if( pIter->iRowidOffset>0 ){
     u8 *a = pIter->pLeaf->p;
     int iOff;
     i64 iDelta;
 
@@ -2248,11 +2252,10 @@
 ** If an error occurs, Fts5Index.rc is set to an appropriate error code. If 
 ** an error has already occurred when this function is called, it is a no-op.
 */
 static void fts5SegIterSeekInit(
   Fts5Index *p,                   /* FTS5 backend */
-  Fts5Buffer *pBuf,               /* Buffer to use for loading pages */
   const u8 *pTerm, int nTerm,     /* Term to seek to */
   int flags,                      /* Mask of FTS5INDEX_XXX flags */
   Fts5StructureSegment *pSeg,     /* Description of segment */
   Fts5SegIter *pIter              /* Object to populate */
 ){
@@ -2635,11 +2638,11 @@
 
 
 /*
 ** Free the iterator object passed as the second argument.
 */
-static void fts5MultiIterFree(Fts5Index *p, Fts5Iter *pIter){
+static void fts5MultiIterFree(Fts5Iter *pIter){
   if( pIter ){
     int i;
     for(i=0; i<pIter->nSeg; i++){
       fts5SegIterClear(&pIter->aSeg[i]);
     }
@@ -2676,11 +2679,10 @@
 ** If non-zero is returned, the caller should call fts5MultiIterAdvanced()
 ** on the iterator instead. That function does the same as this one, except
 ** that it deals with more complicated cases as well.
 */ 
 static int fts5MultiIterAdvanceRowid(
-  Fts5Index *p,                   /* FTS5 backend to iterate within */
   Fts5Iter *pIter,                /* Iterator to update aFirst[] array for */
   int iChanged,                   /* Index of sub-iterator just advanced */
   Fts5SegIter **ppFirst
 ){
   Fts5SegIter *pNew = &pIter->aSeg[iChanged];
@@ -2751,11 +2753,11 @@
     }else{
       pSeg->xNext(p, pSeg, &bNewTerm);
     }
 
     if( pSeg->pLeaf==0 || bNewTerm 
-     || fts5MultiIterAdvanceRowid(p, pIter, iFirst, &pSeg)
+     || fts5MultiIterAdvanceRowid(pIter, iFirst, &pSeg)
     ){
       fts5MultiIterAdvanced(p, pIter, iFirst, 1);
       fts5MultiIterSetEof(pIter);
       pSeg = &pIter->aSeg[pIter->aFirst[1].iFirst];
       if( pSeg->pLeaf==0 ) return;
@@ -2784,11 +2786,11 @@
       int bNewTerm = 0;
 
       assert( p->rc==SQLITE_OK );
       pSeg->xNext(p, pSeg, &bNewTerm);
       if( pSeg->pLeaf==0 || bNewTerm 
-       || fts5MultiIterAdvanceRowid(p, pIter, iFirst, &pSeg)
+       || fts5MultiIterAdvanceRowid(pIter, iFirst, &pSeg)
       ){
         fts5MultiIterAdvanced(p, pIter, iFirst, 1);
         fts5MultiIterSetEof(pIter);
         *pbNewTerm = 1;
       }else{
@@ -2798,11 +2800,12 @@
 
     }while( fts5MultiIterIsEmpty(p, pIter) );
   }
 }
 
-static void fts5IterSetOutputs_Noop(Fts5Iter *pIter, Fts5SegIter *pSeg){
+static void fts5IterSetOutputs_Noop(Fts5Iter *pUnused1, Fts5SegIter *pUnused2){
+  UNUSED_PARAM2(pUnused1, pUnused2);
 }
 
 static Fts5Iter *fts5MultiIterAlloc(
   Fts5Index *p,                   /* FTS5 backend to iterate within */
   int nSeg
@@ -2824,14 +2827,15 @@
   }
   return pNew;
 }
 
 static void fts5PoslistCallback(
-  Fts5Index *p, 
+  Fts5Index *pUnused, 
   void *pContext, 
   const u8 *pChunk, int nChunk
 ){
+  UNUSED_PARAM(pUnused);
   assert_nc( nChunk>=0 );
   if( nChunk>0 ){
     fts5BufferSafeAppendBlob((Fts5Buffer*)pContext, pChunk, nChunk);
   }
 }
@@ -2861,15 +2865,16 @@
   }
   return 0;
 }
 
 static void fts5PoslistOffsetsCallback(
-  Fts5Index *p, 
+  Fts5Index *pUnused, 
   void *pContext, 
   const u8 *pChunk, int nChunk
 ){
   PoslistOffsetsCtx *pCtx = (PoslistOffsetsCtx*)pContext;
+  UNUSED_PARAM(pUnused);
   assert_nc( nChunk>=0 );
   if( nChunk>0 ){
     int i = 0;
     while( i<nChunk ){
       int iVal;
@@ -2883,15 +2888,16 @@
     }
   }
 }
 
 static void fts5PoslistFilterCallback(
-  Fts5Index *p, 
+  Fts5Index *pUnused,
   void *pContext, 
   const u8 *pChunk, int nChunk
 ){
   PoslistCallbackCtx *pCtx = (PoslistCallbackCtx*)pContext;
+  UNUSED_PARAM(pUnused);
   assert_nc( nChunk>=0 );
   if( nChunk>0 ){
     /* Search through to find the first varint with value 1. This is the
     ** start of the next columns hits. */
     int i = 0;
@@ -3251,11 +3257,10 @@
   Fts5Iter **ppOut                /* New object */
 ){
   int nSeg = 0;                   /* Number of segment-iters in use */
   int iIter = 0;                  /* */
   int iSeg;                       /* Used to iterate through segments */
-  Fts5Buffer buf = {0,0,0};       /* Buffer used by fts5SegIterSeekInit() */
   Fts5StructureLevel *pLvl;
   Fts5Iter *pNew;
 
   assert( (pTerm==0 && nTerm==0) || iLevel<0 );
 
@@ -3294,11 +3299,11 @@
           Fts5StructureSegment *pSeg = &pLvl->aSeg[iSeg];
           Fts5SegIter *pIter = &pNew->aSeg[iIter++];
           if( pTerm==0 ){
             fts5SegIterInit(p, pSeg, pIter);
           }else{
-            fts5SegIterSeekInit(p, &buf, pTerm, nTerm, flags, pSeg, pIter);
+            fts5SegIterSeekInit(p, pTerm, nTerm, flags, pSeg, pIter);
           }
         }
       }
     }else{
       pLvl = &pStruct->aLevel[iLevel];
@@ -3331,15 +3336,13 @@
       Fts5SegIter *pSeg = &pNew->aSeg[pNew->aFirst[1].iFirst];
       pNew->xSetOutputs(pNew, pSeg);
     }
 
   }else{
-    fts5MultiIterFree(p, pNew);
+    fts5MultiIterFree(pNew);
     *ppOut = 0;
   }
-  fts5BufferFree(&buf);
-
 }
 
 /*
 ** Create an Fts5Iter that iterates through the doclist provided
 ** as the second argument.
@@ -3473,19 +3476,18 @@
     p->nPendingData = 0;
   }
 }
 
 /*
-** Return the size of the prefix, in bytes, that buffer (nNew/pNew) shares
-** with buffer (nOld/pOld).
+** Return the size of the prefix, in bytes, that buffer 
+** (pNew/<length-unknown>) shares with buffer (pOld/nOld).
+**
+** Buffer (pNew/<length-unknown>) is guaranteed to be greater 
+** than buffer (pOld/nOld).
 */
-static int fts5PrefixCompress(
-  int nOld, const u8 *pOld,
-  int nNew, const u8 *pNew
-){
+static int fts5PrefixCompress(int nOld, const u8 *pOld, const u8 *pNew){
   int i;
-  assert( fts5BlobCompare(pOld, nOld, pNew, nNew)<0 );
   for(i=0; i<nOld; i++){
     if( pOld[i]!=pNew[i] ) break;
   }
   return i;
 }
@@ -3791,17 +3793,17 @@
       ** In this case the previous term is not available, so just write a
       ** copy of (pTerm/nTerm) into the parent node. This is slightly
       ** inefficient, but still correct.  */
       int n = nTerm;
       if( pPage->term.n ){
-        n = 1 + fts5PrefixCompress(pPage->term.n, pPage->term.p, nTerm, pTerm);
+        n = 1 + fts5PrefixCompress(pPage->term.n, pPage->term.p, pTerm);
       }
       fts5WriteBtreeTerm(p, pWriter, n, pTerm);
       pPage = &pWriter->writer;
     }
   }else{
-    nPrefix = fts5PrefixCompress(pPage->term.n, pPage->term.p, nTerm, pTerm);
+    nPrefix = fts5PrefixCompress(pPage->term.n, pPage->term.p, pTerm);
     fts5BufferAppendVarint(&p->rc, &pPage->buf, nPrefix);
   }
 
   /* Append the number of bytes of new data, then the term data itself
   ** to the page. */
@@ -4163,11 +4165,11 @@
     assert( pSeg->pgnoLast>0 );
     fts5TrimSegments(p, pIter);
     pLvl->nMerge = nInput;
   }
 
-  fts5MultiIterFree(p, pIter);
+  fts5MultiIterFree(pIter);
   fts5BufferFree(&term);
   if( pnRem ) *pnRem -= writer.nLeafWritten;
 }
 
 /*
@@ -4539,13 +4541,14 @@
 }
 
 static void fts5AppendRowid(
   Fts5Index *p,
   i64 iDelta,
-  Fts5Iter *pMulti,
+  Fts5Iter *pUnused,
   Fts5Buffer *pBuf
 ){
+  UNUSED_PARAM(pUnused);
   fts5BufferAppendVarint(&p->rc, pBuf, iDelta);
 }
 
 static void fts5AppendPoslist(
   Fts5Index *p,
@@ -4884,11 +4887,11 @@
       if( p->rc==SQLITE_OK ){
         xMerge(p, &doclist, &aBuf[i]);
       }
       fts5BufferFree(&aBuf[i]);
     }
-    fts5MultiIterFree(p, p1);
+    fts5MultiIterFree(p1);
 
     pData = fts5IdxMalloc(p, sizeof(Fts5Data) + doclist.n);
     if( pData ){
       pData->p = (u8*)&pData[1];
       pData->nn = pData->szLeaf = doclist.n;
@@ -5165,11 +5168,11 @@
     }else{
       /* Scan multiple terms in the main index */
       int bDesc = (flags & FTS5INDEX_QUERY_DESC)!=0;
       buf.p[0] = FTS5_MAIN_PREFIX;
       fts5SetupPrefixIter(p, bDesc, buf.p, nToken+1, pColset, &pRet);
-      assert( pRet->pColset==0 );
+      assert( p->rc!=SQLITE_OK || pRet->pColset==0 );
       fts5IterSetOutputCb(&p->rc, pRet);
       if( p->rc==SQLITE_OK ){
         Fts5SegIter *pSeg = &pRet->aSeg[pRet->aFirst[1].iFirst];
         if( pSeg->pLeaf ) pRet->xSetOutputs(pRet, pSeg);
       }
@@ -5248,11 +5251,11 @@
 */
 void sqlite3Fts5IterClose(Fts5IndexIter *pIndexIter){
   if( pIndexIter ){
     Fts5Iter *pIter = (Fts5Iter*)pIndexIter;
     Fts5Index *pIndex = pIter->pIndex;
-    fts5MultiIterFree(pIter->pIndex, pIter);
+    fts5MultiIterFree(pIter);
     fts5CloseReader(pIndex);
   }
 }
 
 /*
@@ -5807,11 +5810,11 @@
       }
     }
   }
   fts5TestTerm(p, &term, 0, 0, cksum2, &cksum3);
 
-  fts5MultiIterFree(p, pIter);
+  fts5MultiIterFree(pIter);
   if( p->rc==SQLITE_OK && cksum!=cksum2 ) p->rc = FTS5_CORRUPT;
 
   fts5StructureRelease(pStruct);
 #ifdef SQLITE_DEBUG
   fts5BufferFree(&term);
@@ -6044,10 +6047,11 @@
   int rc = SQLITE_OK;             /* Return code */
   int nSpace = 0;
   int eDetailNone = (sqlite3_user_data(pCtx)!=0);
 
   assert( nArg==2 );
+  UNUSED_PARAM(nArg);
   memset(&s, 0, sizeof(Fts5Buffer));
   iRowid = sqlite3_value_int64(apVal[0]);
 
   /* Make a copy of the second argument (a blob) in aBlob[]. The aBlob[]
   ** copy is followed by FTS5_DATA_ZERO_PADDING 0x00 bytes, which prevents

Index: ext/fts5/fts5_main.c
==================================================================
--- ext/fts5/fts5_main.c
+++ ext/fts5/fts5_main.c
@@ -1094,11 +1094,11 @@
 **   3. A full-table scan.
 */
 static int fts5FilterMethod(
   sqlite3_vtab_cursor *pCursor,   /* The cursor used for this query */
   int idxNum,                     /* Strategy index */
-  const char *idxStr,             /* Unused */
+  const char *zUnused,            /* Unused */
   int nVal,                       /* Number of elements in apVal */
   sqlite3_value **apVal           /* Arguments for the indexing scheme */
 ){
   Fts5Table *pTab = (Fts5Table*)(pCursor->pVtab);
   Fts5Config *pConfig = pTab->pConfig;
@@ -1111,10 +1111,13 @@
   sqlite3_value *pRank = 0;       /* rank MATCH ? expression (or NULL) */
   sqlite3_value *pRowidEq = 0;    /* rowid = ? expression (or NULL) */
   sqlite3_value *pRowidLe = 0;    /* rowid <= ? expression (or NULL) */
   sqlite3_value *pRowidGe = 0;    /* rowid >= ? expression (or NULL) */
   char **pzErrmsg = pConfig->pzErrmsg;
+
+  UNUSED_PARAM(zUnused);
+  UNUSED_PARAM(nVal);
 
   if( pCsr->ePlan ){
     fts5FreeCursorComponents(pCsr);
     memset(&pCsr->ePlan, 0, sizeof(Fts5Cursor) - ((u8*)&pCsr->ePlan-(u8*)pCsr));
   }
@@ -1396,12 +1399,11 @@
   return rc;
 }
 
 static int fts5SpecialDelete(
   Fts5Table *pTab, 
-  sqlite3_value **apVal, 
-  sqlite3_int64 *piRowid
+  sqlite3_value **apVal
 ){
   int rc = SQLITE_OK;
   int eType1 = sqlite3_value_type(apVal[1]);
   if( eType1==SQLITE_INTEGER ){
     sqlite3_int64 iDel = sqlite3_value_int64(apVal[1]);
@@ -1473,11 +1475,11 @@
     /* A "special" INSERT op. These are handled separately. */
     const char *z = (const char*)sqlite3_value_text(apVal[2+pConfig->nCol]);
     if( pConfig->eContent!=FTS5_CONTENT_NORMAL 
       && 0==sqlite3_stricmp("delete", z) 
     ){
-      rc = fts5SpecialDelete(pTab, apVal, pRowid);
+      rc = fts5SpecialDelete(pTab, apVal);
     }else{
       rc = fts5SpecialInsert(pTab, z, apVal[2 + pConfig->nCol + 1]);
     }
   }else{
     /* A regular INSERT, UPDATE or DELETE statement. The trick here is that
@@ -1574,10 +1576,11 @@
 
 /*
 ** Implementation of xBegin() method. 
 */
 static int fts5BeginMethod(sqlite3_vtab *pVtab){
+  UNUSED_PARAM(pVtab);  /* Call below is a no-op for NDEBUG builds */
   fts5CheckTransactionState((Fts5Table*)pVtab, FTS5_BEGIN, 0);
   return SQLITE_OK;
 }
 
 /*
@@ -1584,10 +1587,11 @@
 ** Implementation of xCommit() method. This is a no-op. The contents of
 ** the pending-terms hash-table have already been flushed into the database
 ** by fts5SyncMethod().
 */
 static int fts5CommitMethod(sqlite3_vtab *pVtab){
+  UNUSED_PARAM(pVtab);  /* Call below is a no-op for NDEBUG builds */
   fts5CheckTransactionState((Fts5Table*)pVtab, FTS5_COMMIT, 0);
   return SQLITE_OK;
 }
 
 /*
@@ -1837,16 +1841,18 @@
 }
 
 static int fts5ColumnSizeCb(
   void *pContext,                 /* Pointer to int */
   int tflags,
-  const char *pToken,             /* Buffer containing token */
-  int nToken,                     /* Size of token in bytes */
-  int iStart,                     /* Start offset of token */
-  int iEnd                        /* End offset of token */
+  const char *pUnused,            /* Buffer containing token */
+  int nUnused,                    /* Size of token in bytes */
+  int iUnused1,                   /* Start offset of token */
+  int iUnused2                    /* End offset of token */
 ){
   int *pCnt = (int*)pContext;
+  UNUSED_PARAM2(pUnused, nUnused);
+  UNUSED_PARAM2(iUnused1, iUnused2);
   if( (tflags & FTS5_TOKEN_COLOCATED)==0 ){
     (*pCnt)++;
   }
   return SQLITE_OK;
 }
@@ -1958,14 +1964,15 @@
 
   return pRet;
 }
 
 static void fts5ApiPhraseNext(
-  Fts5Context *pCtx, 
+  Fts5Context *pUnused, 
   Fts5PhraseIter *pIter, 
   int *piCol, int *piOff
 ){
+  UNUSED_PARAM(pUnused);
   if( pIter->a>=pIter->b ){
     *piCol = -1;
     *piOff = -1;
   }else{
     int iVal;
@@ -2113,16 +2120,15 @@
   int rc;
   Fts5Cursor *pNew = 0;
 
   rc = fts5OpenMethod(pCsr->base.pVtab, (sqlite3_vtab_cursor**)&pNew);
   if( rc==SQLITE_OK ){
-    Fts5Config *pConf = pTab->pConfig;
     pNew->ePlan = FTS5_PLAN_MATCH;
     pNew->iFirstRowid = SMALLEST_INT64;
     pNew->iLastRowid = LARGEST_INT64;
     pNew->base.pVtab = (sqlite3_vtab*)pTab;
-    rc = sqlite3Fts5ExprClonePhrase(pConf, pCsr->pExpr, iPhrase, &pNew->pExpr);
+    rc = sqlite3Fts5ExprClonePhrase(pCsr->pExpr, iPhrase, &pNew->pExpr);
   }
 
   if( rc==SQLITE_OK ){
     for(rc = fts5CursorFirst(pTab, pNew, 0);
         rc==SQLITE_OK && CsrFlagTest(pNew, FTS5CSR_EOF)==0;
@@ -2331,18 +2337,19 @@
 ** This routine implements the xFindFunction method for the FTS3
 ** virtual table.
 */
 static int fts5FindFunctionMethod(
   sqlite3_vtab *pVtab,            /* Virtual table handle */
-  int nArg,                       /* Number of SQL function arguments */
+  int nUnused,                    /* Number of SQL function arguments */
   const char *zName,              /* Name of SQL function */
   void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), /* OUT: Result */
   void **ppArg                    /* OUT: User data for *pxFunc */
 ){
   Fts5Table *pTab = (Fts5Table*)pVtab;
   Fts5Auxiliary *pAux;
 
+  UNUSED_PARAM(nUnused);
   pAux = fts5FindAuxiliary(pTab, zName);
   if( pAux ){
     *pxFunc = fts5ApiCallback;
     *ppArg = (void*)pAux;
     return 1;
@@ -2368,10 +2375,11 @@
 **
 ** Flush the contents of the pending-terms table to disk.
 */
 static int fts5SavepointMethod(sqlite3_vtab *pVtab, int iSavepoint){
   Fts5Table *pTab = (Fts5Table*)pVtab;
+  UNUSED_PARAM(iSavepoint);  /* Call below is a no-op for NDEBUG builds */
   fts5CheckTransactionState(pTab, FTS5_SAVEPOINT, iSavepoint);
   fts5TripCursors(pTab);
   return sqlite3Fts5StorageSync(pTab->pStorage, 0);
 }
 
@@ -2380,10 +2388,11 @@
 **
 ** This is a no-op.
 */
 static int fts5ReleaseMethod(sqlite3_vtab *pVtab, int iSavepoint){
   Fts5Table *pTab = (Fts5Table*)pVtab;
+  UNUSED_PARAM(iSavepoint);  /* Call below is a no-op for NDEBUG builds */
   fts5CheckTransactionState(pTab, FTS5_RELEASE, iSavepoint);
   fts5TripCursors(pTab);
   return sqlite3Fts5StorageSync(pTab->pStorage, 0);
 }
 
@@ -2392,10 +2401,11 @@
 **
 ** Discard the contents of the pending terms table.
 */
 static int fts5RollbackToMethod(sqlite3_vtab *pVtab, int iSavepoint){
   Fts5Table *pTab = (Fts5Table*)pVtab;
+  UNUSED_PARAM(iSavepoint);  /* Call below is a no-op for NDEBUG builds */
   fts5CheckTransactionState(pTab, FTS5_ROLLBACKTO, iSavepoint);
   fts5TripCursors(pTab);
   return sqlite3Fts5StorageRollback(pTab->pStorage);
 }
 
@@ -2571,14 +2581,15 @@
 }
 
 static void fts5Fts5Func(
   sqlite3_context *pCtx,          /* Function call context */
   int nArg,                       /* Number of args */
-  sqlite3_value **apVal           /* Function arguments */
+  sqlite3_value **apUnused        /* Function arguments */
 ){
   Fts5Global *pGlobal = (Fts5Global*)sqlite3_user_data(pCtx);
   char buf[8];
+  UNUSED_PARAM2(nArg, apUnused);
   assert( nArg==0 );
   assert( sizeof(buf)>=sizeof(pGlobal) );
   memcpy(buf, (void*)&pGlobal, sizeof(pGlobal));
   sqlite3_result_blob(pCtx, buf, sizeof(pGlobal), SQLITE_TRANSIENT);
 }
@@ -2587,13 +2598,14 @@
 ** Implementation of fts5_source_id() function.
 */
 static void fts5SourceIdFunc(
   sqlite3_context *pCtx,          /* Function call context */
   int nArg,                       /* Number of args */
-  sqlite3_value **apVal           /* Function arguments */
+  sqlite3_value **apUnused        /* Function arguments */
 ){
   assert( nArg==0 );
+  UNUSED_PARAM2(nArg, apUnused);
   sqlite3_result_text(pCtx, "--FTS5-SOURCE-ID--", -1, SQLITE_TRANSIENT);
 }
 
 static int fts5Init(sqlite3 *db){
   static const sqlite3_module fts5Mod = {

Index: ext/fts5/fts5_storage.c
==================================================================
--- ext/fts5/fts5_storage.c
+++ ext/fts5/fts5_storage.c
@@ -360,15 +360,16 @@
 static int fts5StorageInsertCallback(
   void *pContext,                 /* Pointer to Fts5InsertCtx object */
   int tflags,
   const char *pToken,             /* Buffer containing token */
   int nToken,                     /* Size of token in bytes */
-  int iStart,                     /* Start offset of token */
-  int iEnd                        /* End offset of token */
+  int iUnused1,                   /* Start offset of token */
+  int iUnused2                    /* End offset of token */
 ){
   Fts5InsertCtx *pCtx = (Fts5InsertCtx*)pContext;
   Fts5Index *pIdx = pCtx->pStorage->pIndex;
+  UNUSED_PARAM2(iUnused1, iUnused2);
   if( (tflags & FTS5_TOKEN_COLOCATED)==0 || pCtx->szCol==0 ){
     pCtx->szCol++;
   }
   return sqlite3Fts5IndexWrite(pIdx, pCtx->iCol, pCtx->szCol-1, pToken, nToken);
 }
@@ -795,20 +796,22 @@
 static int fts5StorageIntegrityCallback(
   void *pContext,                 /* Pointer to Fts5IntegrityCtx object */
   int tflags,
   const char *pToken,             /* Buffer containing token */
   int nToken,                     /* Size of token in bytes */
-  int iStart,                     /* Start offset of token */
-  int iEnd                        /* End offset of token */
+  int iUnused1,                   /* Start offset of token */
+  int iUnused2                    /* End offset of token */
 ){
   Fts5IntegrityCtx *pCtx = (Fts5IntegrityCtx*)pContext;
   Fts5Termset *pTermset = pCtx->pTermset;
   int bPresent;
   int ii;
   int rc = SQLITE_OK;
   int iPos;
   int iCol;
+
+  UNUSED_PARAM2(iUnused1, iUnused2);
 
   if( (tflags & FTS5_TOKEN_COLOCATED)==0 || pCtx->szCol==0 ){
     pCtx->szCol++;
   }
 

Index: ext/fts5/fts5_tokenize.c
==================================================================
--- ext/fts5/fts5_tokenize.c
+++ ext/fts5/fts5_tokenize.c
@@ -60,16 +60,17 @@
 
 /*
 ** Create an "ascii" tokenizer.
 */
 static int fts5AsciiCreate(
-  void *pCtx, 
+  void *pUnused, 
   const char **azArg, int nArg,
   Fts5Tokenizer **ppOut
 ){
   int rc = SQLITE_OK;
   AsciiTokenizer *p = 0;
+  UNUSED_PARAM(pUnused);
   if( nArg%2 ){
     rc = SQLITE_ERROR;
   }else{
     p = sqlite3_malloc(sizeof(AsciiTokenizer));
     if( p==0 ){
@@ -114,11 +115,11 @@
 ** Tokenize some text using the ascii tokenizer.
 */
 static int fts5AsciiTokenize(
   Fts5Tokenizer *pTokenizer,
   void *pCtx,
-  int flags,
+  int iUnused,
   const char *pText, int nText,
   int (*xToken)(void*, int, const char*, int nToken, int iStart, int iEnd)
 ){
   AsciiTokenizer *p = (AsciiTokenizer*)pTokenizer;
   int rc = SQLITE_OK;
@@ -127,10 +128,12 @@
 
   char aFold[64];
   int nFold = sizeof(aFold);
   char *pFold = aFold;
   unsigned char *a = p->aTokenChar;
+
+  UNUSED_PARAM(iUnused);
 
   while( is<nText && rc==SQLITE_OK ){
     int nByte;
 
     /* Skip any leading divider characters. */
@@ -321,16 +324,18 @@
 
 /*
 ** Create a "unicode61" tokenizer.
 */
 static int fts5UnicodeCreate(
-  void *pCtx, 
+  void *pUnused, 
   const char **azArg, int nArg,
   Fts5Tokenizer **ppOut
 ){
   int rc = SQLITE_OK;             /* Return code */
   Unicode61Tokenizer *p = 0;      /* New tokenizer object */ 
+
+  UNUSED_PARAM(pUnused);
 
   if( nArg%2 ){
     rc = SQLITE_ERROR;
   }else{
     p = (Unicode61Tokenizer*)sqlite3_malloc(sizeof(Unicode61Tokenizer));
@@ -384,11 +389,11 @@
 }
 
 static int fts5UnicodeTokenize(
   Fts5Tokenizer *pTokenizer,
   void *pCtx,
-  int flags,
+  int iUnused,
   const char *pText, int nText,
   int (*xToken)(void*, int, const char*, int nToken, int iStart, int iEnd)
 ){
   Unicode61Tokenizer *p = (Unicode61Tokenizer*)pTokenizer;
   int rc = SQLITE_OK;
@@ -399,10 +404,12 @@
 
   /* Output buffer */
   char *aFold = p->aFold;
   int nFold = p->nFold;
   const char *pEnd = &aFold[nFold-6];
+
+  UNUSED_PARAM(iUnused);
 
   /* Each iteration of this loop gobbles up a contiguous run of separators,
   ** then the next token.  */
   while( rc==SQLITE_OK ){
     int iCode;                    /* non-ASCII codepoint read from input */

Index: ext/fts5/fts5_unicode2.c
==================================================================
--- ext/fts5/fts5_unicode2.c
+++ ext/fts5/fts5_unicode2.c
@@ -123,13 +123,13 @@
   };
   static const unsigned int aAscii[4] = {
     0xFFFFFFFF, 0xFC00FFFF, 0xF8000001, 0xF8000001,
   };
 
-  if( c<128 ){
+  if( (unsigned int)c<128 ){
     return ( (aAscii[c >> 5] & (1 << (c & 0x001F)))==0 );
-  }else if( c<(1<<22) ){
+  }else if( (unsigned int)c<(1<<22) ){
     unsigned int key = (((unsigned int)c)<<10) | 0x000003FF;
     int iRes = 0;
     int iHi = sizeof(aEntry)/sizeof(aEntry[0]) - 1;
     int iLo = 0;
     while( iHi>=iLo ){

Index: ext/fts5/fts5_vocab.c
==================================================================
--- ext/fts5/fts5_vocab.c
+++ ext/fts5/fts5_vocab.c
@@ -235,19 +235,21 @@
 
 /* 
 ** Implementation of the xBestIndex method.
 */
 static int fts5VocabBestIndexMethod(
-  sqlite3_vtab *pVTab, 
+  sqlite3_vtab *pUnused,
   sqlite3_index_info *pInfo
 ){
   int i;
   int iTermEq = -1;
   int iTermGe = -1;
   int iTermLe = -1;
   int idxNum = 0;
   int nArg = 0;
+
+  UNUSED_PARAM(pUnused);
 
   for(i=0; i<pInfo->nConstraint; i++){
     struct sqlite3_index_constraint *p = &pInfo->aConstraint[i];
     if( p->usable==0 ) continue;
     if( p->iColumn==0 ){          /* term column */
@@ -486,12 +488,12 @@
 ** This is the xFilter implementation for the virtual table.
 */
 static int fts5VocabFilterMethod(
   sqlite3_vtab_cursor *pCursor,   /* The cursor used for this query */
   int idxNum,                     /* Strategy index */
-  const char *idxStr,             /* Unused */
-  int nVal,                       /* Number of elements in apVal */
+  const char *zUnused,            /* Unused */
+  int nUnused,                    /* Number of elements in apVal */
   sqlite3_value **apVal           /* Arguments for the indexing scheme */
 ){
   Fts5VocabCursor *pCsr = (Fts5VocabCursor*)pCursor;
   int rc = SQLITE_OK;
 
@@ -501,10 +503,12 @@
   int nTerm = 0;
 
   sqlite3_value *pEq = 0;
   sqlite3_value *pGe = 0;
   sqlite3_value *pLe = 0;
+
+  UNUSED_PARAM2(zUnused, nUnused);
 
   fts5VocabResetCursor(pCsr);
   if( idxNum & FTS5_VOCAB_TERM_EQ ) pEq = apVal[iVal++];
   if( idxNum & FTS5_VOCAB_TERM_GE ) pGe = apVal[iVal++];
   if( idxNum & FTS5_VOCAB_TERM_LE ) pLe = apVal[iVal++];

Index: ext/fts5/fts5parse.y
==================================================================
--- ext/fts5/fts5parse.y
+++ ext/fts5/fts5parse.y
@@ -26,16 +26,18 @@
 %extra_argument {Fts5Parse *pParse}
 
 // This code runs whenever there is a syntax error
 //
 %syntax_error {
+  UNUSED_PARAM(yymajor); /* Silence a compiler warning */
   sqlite3Fts5ParseError(
     pParse, "fts5: syntax error near \"%.*s\"",TOKEN.n,TOKEN.p
   );
 }
 %stack_overflow {
-  assert( 0 );
+  UNUSED_PARAM(yypMinor); /* Silence a compiler warning */
+  sqlite3Fts5ParseError(pParse, "fts5: parser stack overflow");
 }
 
 // The name of the generated procedure that implements the parser
 // is as follows:
 %name sqlite3Fts5Parser

Index: ext/fts5/test/fts5corrupt3.test
==================================================================
--- ext/fts5/test/fts5corrupt3.test
+++ ext/fts5/test/fts5corrupt3.test
@@ -332,15 +332,12 @@
 do_catchsql_test 6.3.5 {
   INSERT INTO t1(t1) VALUES('integrity-check');
 } {1 {database disk image is malformed}}
 
 
-}
-
 #------------------------------------------------------------------------
 #
-reset_db
 reset_db
 proc rnddoc {n} {
   set map [list a b c d]
   set doc [list]
   for {set i 0} {$i < $n} {incr i} {
@@ -369,8 +366,43 @@
     if {$r != "1 {database disk image is malformed}"} { error $r }
     db eval ROLLBACK  
   }
 } {}
 
+}
+
+#------------------------------------------------------------------------
+# Corruption within the structure record.
+#
+reset_db
+do_execsql_test 8.1 {
+  CREATE VIRTUAL TABLE t1 USING fts5(x, y);
+  INSERT INTO t1 VALUES('one', 'two');
+}
+
+do_test 9.1.1 {
+  set    blob "12345678"    ;# cookie
+  append blob "0105"        ;# 1 level, total of 5 segments
+  append blob "06"          ;# write counter
+  append blob "0002"        ;# first level has 0 segments merging, 2 other.
+  append blob "450108"      ;# first segment
+  execsql "REPLACE INTO t1_data VALUES(10, X'$blob')"
+} {}
+do_catchsql_test 9.1.2 {
+  SELECT * FROM t1('one AND two');
+} {1 {database disk image is malformed}}
+
+do_test 9.2.1 {
+  set    blob "12345678"    ;# cookie
+  append blob "0205"        ;# 2 levels, total of 5 segments
+  append blob "06"          ;# write counter
+  append blob "0001"        ;# first level has 0 segments merging, 1 other.
+  append blob "450108"      ;# first segment
+  execsql "REPLACE INTO t1_data VALUES(10, X'$blob')"
+} {}
+do_catchsql_test 9.2.2 {
+  SELECT * FROM t1('one AND two');
+} {1 {database disk image is malformed}}
+
 sqlite3_fts5_may_be_corrupt 0
 finish_test
 

Index: ext/fts5/test/fts5hash.test
==================================================================
--- ext/fts5/test/fts5hash.test
+++ ext/fts5/test/fts5hash.test
@@ -64,51 +64,70 @@
   return $doc
 }
 
 foreach_detail_mode $testprefix {
 
-set vocab [build_vocab1]
-db func r random_doc 
-
-do_execsql_test 1.0 {
-  CREATE VIRTUAL TABLE eee USING fts5(e, ee, detail=%DETAIL%);
-  BEGIN;
-    WITH ii(i) AS (SELECT 1 UNION ALL SELECT i+1 FROM ii WHERE i<100)
-    INSERT INTO eee SELECT r($vocab, 5), r($vocab, 7) FROM ii;
-    INSERT INTO eee(eee) VALUES('integrity-check');
-  COMMIT;
-  INSERT INTO eee(eee) VALUES('integrity-check');
-}
-
-set hash [sqlite3_fts5_token_hash 1024 xyz]
-set vocab [build_vocab1 -prefix xyz -hash $hash]
-lappend vocab xyz
-
-do_execsql_test 1.1 {
-  CREATE VIRTUAL TABLE vocab USING fts5vocab(eee, 'row'); 
-  BEGIN;
-}
-do_test 1.2 {
-  for {set i 1} {$i <= 100} {incr i} {
-    execsql { INSERT INTO eee VALUES( r($vocab, 5), r($vocab, 7) ) }
-  }
-} {}
-  
-do_test 1.3 {
-  db eval { SELECT term, doc FROM vocab } {
-    set nRow [db one {SELECT count(*) FROM eee WHERE eee MATCH $term}]
-    if {$nRow != $doc} {
-      error "term=$term fts5vocab=$doc cnt=$nRow"
-    }
-  }
-  set {} {}
-} {}
-
-do_execsql_test 1.4 {
-  COMMIT;
-  INSERT INTO eee(eee) VALUES('integrity-check');
-}
+  set vocab [build_vocab1]
+  db func r random_doc 
+  
+  do_execsql_test 1.0 {
+    CREATE VIRTUAL TABLE eee USING fts5(e, ee, detail=%DETAIL%);
+    BEGIN;
+      WITH ii(i) AS (SELECT 1 UNION ALL SELECT i+1 FROM ii WHERE i<100)
+      INSERT INTO eee SELECT r($vocab, 5), r($vocab, 7) FROM ii;
+      INSERT INTO eee(eee) VALUES('integrity-check');
+    COMMIT;
+    INSERT INTO eee(eee) VALUES('integrity-check');
+  }
+  
+  set hash [sqlite3_fts5_token_hash 1024 xyz]
+  set vocab [build_vocab1 -prefix xyz -hash $hash]
+  lappend vocab xyz
+  
+  do_execsql_test 1.1 {
+    CREATE VIRTUAL TABLE vocab USING fts5vocab(eee, 'row'); 
+    BEGIN;
+  }
+  do_test 1.2 {
+    for {set i 1} {$i <= 100} {incr i} {
+      execsql { INSERT INTO eee VALUES( r($vocab, 5), r($vocab, 7) ) }
+    }
+  } {}
+    
+  do_test 1.3 {
+    db eval { SELECT term, doc FROM vocab } {
+      set nRow [db one {SELECT count(*) FROM eee WHERE eee MATCH $term}]
+      if {$nRow != $doc} {
+        error "term=$term fts5vocab=$doc cnt=$nRow"
+      }
+    }
+    set {} {}
+  } {}
+  
+  do_execsql_test 1.4 {
+    COMMIT;
+    INSERT INTO eee(eee) VALUES('integrity-check');
+  }
+
+  #-----------------------------------------------------------------------
+  # Add a small and very large token with the same hash value to an
+  # empty table. At one point this would provoke an asan error.
+  #
+  do_test 2.0 {
+    set big [string repeat 12345 40]
+    set hash [sqlite3_fts5_token_hash 1024 $big]
+    while {1} {
+      set small [random_token]
+      if {[sqlite3_fts5_token_hash 1024 $small]==$hash} break
+    }
+
+    execsql { CREATE VIRTUAL TABLE t2 USING fts5(x, detail=%DETAIL%) }
+breakpoint
+    execsql {
+      INSERT INTO t2 VALUES($small || ' ' || $big);
+    }
+  } {}
 
 } ;# foreach_detail_mode
 
 finish_test
 

Index: ext/fts5/test/fts5simple.test
==================================================================
--- ext/fts5/test/fts5simple.test
+++ ext/fts5/test/fts5simple.test
@@ -396,8 +396,18 @@
 #-------------------------------------------------------------------------
 do_execsql_test 18.1 {
   CREATE VIRTUAL TABLE x4 USING fts5(x);
   SELECT rowid FROM x4('""');
 }
+
+#-------------------------------------------------------------------------
+reset_db
+do_execsql_test 19.1 {
+  CREATE VIRTUAL TABLE x1 USING fts5(a,b,c);
+}
+
+do_catchsql_test 19.2 {
+  SELECT * FROM x1 WHERE x1 MATCH 'c0 AND (c1 AND (c2 AND (c3 AND (c4 AND (c5 AND (c6 AND (c7 AND (c8 AND (c9 AND (c10 AND (c11 AND (c12 AND (c13 AND (c14 AND (c15 AND (c16 AND (c17 AND (c18 AND (c19 AND (c20 AND (c21 AND (c22 AND (c23 AND (c24 AND (c25 AND (c26 AND (c27 AND (c28 AND (c29 AND (c30 AND (c31 AND (c32 AND (c33 AND (c34 AND (c35 AND (c36 AND (c37 AND (c38 AND (c39 AND (c40 AND (c41 AND (c42 AND (c43 AND (c44 AND (c45 AND (c46 AND (c47 AND (c48 AND (c49 AND (c50 AND (c51 AND (c52 AND (c53 AND (c54 AND (c55 AND (c56 AND (c57 AND (c58 AND (c59 AND (c60 AND (c61 AND (c62 AND (c63 AND (c64 AND (c65 AND (c66 AND (c67 AND (c68 AND (c69 AND (c70 AND (c71 AND (c72 AND (c73 AND (c74 AND (c75 AND (c76 AND (c77 AND (c78 AND (c79 AND (c80 AND (c81 AND (c82 AND (c83 AND (c84 AND (c85 AND (c86 AND (c87 AND (c88 AND (c89 AND (c90 AND (c91 AND (c92 AND (c93 AND (c94 AND (c95 AND (c96 AND (c97 AND (c98 AND (c99 AND (c100 AND (c101 AND (c102 AND (c103 AND (c104 AND (c105 AND (c106 AND (c107 AND (c108 AND (c109 AND (c110 AND (c111 AND (c112 AND (c113 AND (c114 AND (c115 AND (c116 AND (c117 AND (c118 AND (c119 AND (c120 AND (c121 AND (c122 AND (c123 AND (c124 AND (c125 AND (c126 AND (c127 AND (c128 AND (c129 AND (c130 AND (c131 AND (c132 AND (c133 AND (c134 AND (c135 AND (c136 AND (c137 AND (c138 AND (c139 AND (c140 AND (c141 AND (c142 AND (c143 AND (c144 AND (c145 AND (c146 AND (c147 AND (c148 AND (c149 AND (c150 AND (c151 AND (c152 AND (c153 AND (c154 AND (c155 AND (c156 AND (c157 AND (c158 AND (c159 AND (c160 AND (c161 AND (c162 AND (c163 AND (c164 AND (c165 AND (c166 AND (c167 AND (c168 AND (c169 AND (c170 AND (c171 AND (c172 AND (c173 AND (c174 AND (c175 AND (c176 AND (c177 AND (c178 AND (c179 AND (c180 AND (c181 AND (c182 AND (c183 AND (c184 AND (c185 AND (c186 AND (c187 AND (c188 AND (c189 AND (c190 AND (c191 AND (c192 AND (c193 AND (c194 AND (c195 AND (c196 AND (c197 AND (c198 AND (c199 AND c200)))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))';
+} {1 {fts5: parser stack overflow}}
 
 finish_test
 

Index: ext/misc/json1.c
==================================================================
--- ext/misc/json1.c
+++ ext/misc/json1.c
@@ -29,11 +29,15 @@
 #include <assert.h>
 #include <string.h>
 #include <stdlib.h>
 #include <stdarg.h>
 
-#define UNUSED_PARAM(X)  (void)(X)
+/* Mark a function parameter as unused, to suppress nuisance compiler
+** warnings. */
+#ifndef UNUSED_PARAM
+# define UNUSED_PARAM(X)  (void)(X)
+#endif
 
 #ifndef LARGEST_INT64
 # define LARGEST_INT64  (0xffffffff|(((sqlite3_int64)0x7fffffff)<<32))
 # define SMALLEST_INT64 (((sqlite3_int64)-1) - LARGEST_INT64)
 #endif
@@ -1550,10 +1554,11 @@
   sqlite3_context *ctx,
   int argc,
   sqlite3_value **argv
 ){
   JsonString *pStr;
+  UNUSED_PARAM(argc);
   pStr = (JsonString*)sqlite3_aggregate_context(ctx, sizeof(*pStr));
   if( pStr ){
     if( pStr->zBuf==0 ){
       jsonInit(pStr, ctx);
       jsonAppendChar(pStr, '[');
@@ -1595,10 +1600,11 @@
   sqlite3_value **argv
 ){
   JsonString *pStr;
   const char *z;
   u32 n;
+  UNUSED_PARAM(argc);
   pStr = (JsonString*)sqlite3_aggregate_context(ctx, sizeof(*pStr));
   if( pStr ){
     if( pStr->zBuf==0 ){
       jsonInit(pStr, ctx);
       jsonAppendChar(pStr, '{');

Index: main.mk
==================================================================
--- main.mk
+++ main.mk
@@ -485,14 +485,13 @@
 
 mptester$(EXE):	sqlite3.c $(TOP)/mptest/mptest.c
 	$(TCCX) -o $@ -I. $(TOP)/mptest/mptest.c sqlite3.c \
 		$(TLIBS) $(THREADLIB)
 
-MPTEST1=./mptester$(EXE) mptest.db $(TOP)/mptest/crash01.test --repeat 20
-MPTEST2=./mptester$(EXE) mptest.db $(TOP)/mptest/multiwrite01.test --repeat 20
+MPTEST1=./mptester$(EXE) mptest1.db $(TOP)/mptest/crash01.test --repeat 20
+MPTEST2=./mptester$(EXE) mptest2.db $(TOP)/mptest/multiwrite01.test --repeat 20
 mptest:	mptester$(EXE)
-	rm -f mptest.db
 	$(MPTEST1) --journalmode DELETE
 	$(MPTEST2) --journalmode WAL
 	$(MPTEST1) --journalmode WAL
 	$(MPTEST2) --journalmode PERSIST
 	$(MPTEST1) --journalmode PERSIST
@@ -848,14 +847,19 @@
 # releasetest.tcl script.
 #
 checksymbols: sqlite3.o
 	nm -g --defined-only sqlite3.o | grep -v " sqlite3_" ; test $$? -ne 0
 
-# Build the amalgamation-autoconf package.
+# Build the amalgamation-autoconf package.  The amalamgation-tarball target builds
+# a tarball named for the version number.  Ex:  sqlite-autoconf-3110000.tar.gz.
+# The snapshot-tarball target builds a tarball named by the SHA1 hash
 #
 amalgamation-tarball: sqlite3.c
-	TOP=$(TOP) sh $(TOP)/tool/mkautoconfamal.sh
+	TOP=$(TOP) sh $(TOP)/tool/mkautoconfamal.sh --normal
+
+snapshot-tarball: sqlite3.c
+	TOP=$(TOP) sh $(TOP)/tool/mkautoconfamal.sh --snapshot
 
 
 # Standard install and cleanup targets
 #
 install:	sqlite3 libsqlite3.a sqlite3.h

Index: mptest/mptest.c
==================================================================
--- mptest/mptest.c
+++ mptest/mptest.c
@@ -39,10 +39,11 @@
 # define WIN32_LEAN_AND_MEAN
 # include <windows.h>
 #else
 # include <unistd.h>
 #endif
+#include <errno.h>
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
 #include <ctype.h>
 
@@ -1242,10 +1243,23 @@
   const char *zTail = argv0;
   for(i=0; argv0[i]; i++){
     if( isDirSep(argv0[i]) ) zTail = argv0+i+1;
   }
   fprintf(stderr,"Usage: %s DATABASE ?OPTIONS? ?SCRIPT?\n", zTail);
+  fprintf(stderr,
+    "Options:\n"
+    "   --errlog FILENAME           Write errors to FILENAME\n"
+    "   --journalmode MODE          Use MODE as the journal_mode\n"
+    "   --log FILENAME              Log messages to FILENAME\n"
+    "   --quiet                     Suppress unnecessary output\n"
+    "   --vfs NAME                  Use NAME as the VFS\n"
+    "   --repeat N                  Repeat the test N times\n"
+    "   --sqltrace                  Enable SQL tracing\n"
+    "   --sync                      Enable synchronous disk writes\n"
+    "   --timeout MILLISEC          Busy timeout is MILLISEC\n"
+    "   --trace BOOLEAN             Enable or disable tracing\n"
+  );
   exit(1);
 }
 
 /* Report on unrecognized arguments */
 static void unrecognizedArguments(
@@ -1273,10 +1287,12 @@
   const char *zTrace;
   const char *zCOption;
   const char *zJMode;
   const char *zNRep;
   int nRep = 1, iRep;
+  int iTmout = 0;              /* Default: no timeout */
+  const char *zTmout;
 
   g.argv0 = argv[0];
   g.iTrace = 1;
   if( argc<2 ) usage(argv[0]);
   g.zDbFile = argv[1];
@@ -1299,10 +1315,12 @@
   g.zErrLog = findOption(argv+2, &n, "errlog", 1);
   g.zLog = findOption(argv+2, &n, "log", 1);
   zTrace = findOption(argv+2, &n, "trace", 1);
   if( zTrace ) g.iTrace = atoi(zTrace);
   if( findOption(argv+2, &n, "quiet", 0)!=0 ) g.iTrace = 0;
+  zTmout = findOption(argv+2, &n, "timeout", 1);
+  if( zTmout ) iTmout = atoi(zTmout);
   g.bSqlTrace = findOption(argv+2, &n, "sqltrace", 0)!=0;
   g.bSync = findOption(argv+2, &n, "sync", 0)!=0;
   if( g.zErrLog ){
     g.pErrLog = fopen(g.zErrLog, "a");
   }else{
@@ -1319,10 +1337,11 @@
     iClient = atoi(zClient);
     if( iClient<1 ) fatalError("illegal client number: %d\n", iClient);
     sqlite3_snprintf(sizeof(g.zName), g.zName, "%05d.client%02d",
                      GETPID(), iClient);
   }else{
+    int nTry = 0;
     if( g.iTrace>0 ){
       printf("BEGIN: %s", argv[0]);
       for(i=1; i<argc; i++) printf(" %s", argv[i]);
       printf("\n");
       printf("With SQLite " SQLITE_VERSION " " SQLITE_SOURCE_ID "\n" );
@@ -1330,15 +1349,26 @@
         printf("-DSQLITE_%s\n", zCOption);
       }
       fflush(stdout);
     }
     iClient =  0;
-    unlink(g.zDbFile);
+    do{
+      if( (nTry%5)==4 ) printf("... %strying to unlink '%s'\n",
+                               nTry>5 ? "still " : "", g.zDbFile);
+      rc = unlink(g.zDbFile);
+      if( rc && errno==ENOENT ) rc = 0;
+    }while( rc!=0 && (++nTry)<60 && sqlite3_sleep(1000)>0 );
+    if( rc!=0 ){
+      fatalError("unable to unlink '%s' after %d attempts\n",
+                 g.zDbFile, nTry);
+    }
     openFlags |= SQLITE_OPEN_CREATE;
   }
   rc = sqlite3_open_v2(g.zDbFile, &g.db, openFlags, g.zVfs);
   if( rc ) fatalError("cannot open [%s]", g.zDbFile);
+  if( iTmout>0 ) sqlite3_busy_timeout(g.db, iTmout);
+  
   if( zJMode ){
 #if defined(_WIN32)
     if( sqlite3_stricmp(zJMode,"persist")==0
      || sqlite3_stricmp(zJMode,"truncate")==0
     ){

Index: src/alter.c
==================================================================
--- src/alter.c
+++ src/alter.c
@@ -586,37 +586,10 @@
   sqlite3SrcListDelete(db, pSrc);
   sqlite3DbFree(db, zName);
   db->flags = savedDbFlags;
 }
 
-
-/*
-** Generate code to make sure the file format number is at least minFormat.
-** The generated code will increase the file format number if necessary.
-*/
-void sqlite3MinimumFileFormat(Parse *pParse, int iDb, int minFormat){
-  Vdbe *v;
-  v = sqlite3GetVdbe(pParse);
-  /* The VDBE should have been allocated before this routine is called.
-  ** If that allocation failed, we would have quit before reaching this
-  ** point */
-  if( ALWAYS(v) ){
-    int r1 = sqlite3GetTempReg(pParse);
-    int r2 = sqlite3GetTempReg(pParse);
-    int addr1;
-    sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, BTREE_FILE_FORMAT);
-    sqlite3VdbeUsesBtree(v, iDb);
-    sqlite3VdbeAddOp2(v, OP_Integer, minFormat, r2);
-    addr1 = sqlite3VdbeAddOp3(v, OP_Ge, r2, 0, r1);
-    sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); VdbeCoverage(v);
-    sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, minFormat);
-    sqlite3VdbeJumpHere(v, addr1);
-    sqlite3ReleaseTempReg(pParse, r1);
-    sqlite3ReleaseTempReg(pParse, r2);
-  }
-}
-
 /*
 ** This function is called after an "ALTER TABLE ... ADD" statement
 ** has been parsed. Argument pColDef contains the text of the new
 ** column definition.
 **
@@ -631,13 +604,15 @@
   const char *zTab;         /* Table name */
   char *zCol;               /* Null-terminated column definition */
   Column *pCol;             /* The new column */
   Expr *pDflt;              /* Default value for the new column */
   sqlite3 *db;              /* The database connection; */
+  Vdbe *v = pParse->pVdbe;  /* The prepared statement under construction */
 
   db = pParse->db;
   if( pParse->nErr || db->mallocFailed ) return;
+  assert( v!=0 );
   pNew = pParse->pNewTable;
   assert( pNew );
 
   assert( sqlite3BtreeHoldsAllMutexes(db) );
   iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
@@ -723,15 +698,20 @@
     );
     sqlite3DbFree(db, zCol);
     db->flags = savedDbFlags;
   }
 
-  /* If the default value of the new column is NULL, then set the file
+  /* If the default value of the new column is NULL, then the file
   ** format to 2. If the default value of the new column is not NULL,
-  ** the file format becomes 3.
+  ** the file format be 3.  Back when this feature was first added
+  ** in 2006, we went to the trouble to upgrade the file format to the
+  ** minimum support values.  But 10-years on, we can assume that all
+  ** extent versions of SQLite support file-format 4, so we always and
+  ** unconditionally upgrade to 4.
   */
-  sqlite3MinimumFileFormat(pParse, iDb, pDflt ? 3 : 2);
+  sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, 
+                    SQLITE_MAX_FILE_FORMAT);
 
   /* Reload the schema of the modified table. */
   reloadTableSchema(pParse, pTab, pTab->zName);
 }
 

Index: src/insert.c
==================================================================
--- src/insert.c
+++ src/insert.c
@@ -993,11 +993,11 @@
     }else
 #endif
     {
       int isReplace;    /* Set to true if constraints may cause a replace */
       sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
-          regIns, 0, ipkColumn>=0, onError, endOfLoop, &isReplace
+          regIns, 0, ipkColumn>=0, onError, endOfLoop, &isReplace, 0
       );
       sqlite3FkCheck(pParse, pTab, 0, regIns, 0, 0);
       sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur,
                                regIns, aRegIdx, 0, appendFlag, isReplace==0);
     }
@@ -1074,10 +1074,63 @@
  #undef pTrigger
 #endif
 #ifdef tmask
  #undef tmask
 #endif
+
+/*
+** Meanings of bits in of pWalker->eCode for checkConstraintUnchanged()
+*/
+#define CKCNSTRNT_COLUMN   0x01    /* CHECK constraint uses a changing column */
+#define CKCNSTRNT_ROWID    0x02    /* CHECK constraint references the ROWID */
+
+/* This is the Walker callback from checkConstraintUnchanged().  Set
+** bit 0x01 of pWalker->eCode if
+** pWalker->eCode to 0 if this expression node references any of the
+** columns that are being modifed by an UPDATE statement.
+*/
+static int checkConstraintExprNode(Walker *pWalker, Expr *pExpr){
+  if( pExpr->op==TK_COLUMN ){
+    assert( pExpr->iColumn>=0 || pExpr->iColumn==-1 );
+    if( pExpr->iColumn>=0 ){
+      if( pWalker->u.aiCol[pExpr->iColumn]>=0 ){
+        pWalker->eCode |= CKCNSTRNT_COLUMN;
+      }
+    }else{
+      pWalker->eCode |= CKCNSTRNT_ROWID;
+    }
+  }
+  return WRC_Continue;
+}
+
+/*
+** pExpr is a CHECK constraint on a row that is being UPDATE-ed.  The
+** only columns that are modified by the UPDATE are those for which
+** aiChng[i]>=0, and also the ROWID is modified if chngRowid is true.
+**
+** Return true if CHECK constraint pExpr does not use any of the
+** changing columns (or the rowid if it is changing).  In other words,
+** return true if this CHECK constraint can be skipped when validating
+** the new row in the UPDATE statement.
+*/
+static int checkConstraintUnchanged(Expr *pExpr, int *aiChng, int chngRowid){
+  Walker w;
+  memset(&w, 0, sizeof(w));
+  w.eCode = 0;
+  w.xExprCallback = checkConstraintExprNode;
+  w.u.aiCol = aiChng;
+  sqlite3WalkExpr(&w, pExpr);
+  if( !chngRowid ){
+    testcase( (w.eCode & CKCNSTRNT_ROWID)!=0 );
+    w.eCode &= ~CKCNSTRNT_ROWID;
+  }
+  testcase( w.eCode==0 );
+  testcase( w.eCode==CKCNSTRNT_COLUMN );
+  testcase( w.eCode==CKCNSTRNT_ROWID );
+  testcase( w.eCode==(CKCNSTRNT_ROWID|CKCNSTRNT_COLUMN) );
+  return !w.eCode;
+}
 
 /*
 ** Generate code to do constraint checks prior to an INSERT or an UPDATE
 ** on table pTab.
 **
@@ -1169,11 +1222,12 @@
   int regNewData,      /* First register in a range holding values to insert */
   int regOldData,      /* Previous content.  0 for INSERTs */
   u8 pkChng,           /* Non-zero if the rowid or PRIMARY KEY changed */
   u8 overrideError,    /* Override onError to this if not OE_Default */
   int ignoreDest,      /* Jump to this label on an OE_Ignore resolution */
-  int *pbMayReplace    /* OUT: Set to true if constraint may cause a replace */
+  int *pbMayReplace,   /* OUT: Set to true if constraint may cause a replace */
+  int *aiChng          /* column i is unchanged if aiChng[i]<0 */
 ){
   Vdbe *v;             /* VDBE under constrution */
   Index *pIdx;         /* Pointer to one of the indices */
   Index *pPk = 0;      /* The PRIMARY KEY index */
   sqlite3 *db;         /* Database connection */
@@ -1215,14 +1269,18 @@
 
   /* Test all NOT NULL constraints.
   */
   for(i=0; i<nCol; i++){
     if( i==pTab->iPKey ){
+      continue;        /* ROWID is never NULL */
+    }
+    if( aiChng && aiChng[i]<0 ){
+      /* Don't bother checking for NOT NULL on columns that do not change */
       continue;
     }
     onError = pTab->aCol[i].notNull;
-    if( onError==OE_None ) continue;
+    if( onError==OE_None ) continue;  /* This column is allowed to be NULL */
     if( overrideError!=OE_Default ){
       onError = overrideError;
     }else if( onError==OE_Default ){
       onError = OE_Abort;
     }
@@ -1267,12 +1325,15 @@
   if( pTab->pCheck && (db->flags & SQLITE_IgnoreChecks)==0 ){
     ExprList *pCheck = pTab->pCheck;
     pParse->ckBase = regNewData+1;
     onError = overrideError!=OE_Default ? overrideError : OE_Abort;
     for(i=0; i<pCheck->nExpr; i++){
-      int allOk = sqlite3VdbeMakeLabel(v);
-      sqlite3ExprIfTrue(pParse, pCheck->a[i].pExpr, allOk, SQLITE_JUMPIFNULL);
+      int allOk;
+      Expr *pExpr = pCheck->a[i].pExpr;
+      if( aiChng && checkConstraintUnchanged(pExpr, aiChng, pkChng) ) continue;
+      allOk = sqlite3VdbeMakeLabel(v);
+      sqlite3ExprIfTrue(pParse, pExpr, allOk, SQLITE_JUMPIFNULL);
       if( onError==OE_Ignore ){
         sqlite3VdbeGoto(v, ignoreDest);
       }else{
         char *zName = pCheck->a[i].zName;
         if( zName==0 ) zName = pTab->zName;

Index: src/os.c
==================================================================
--- src/os.c
+++ src/os.c
@@ -15,18 +15,40 @@
 */
 #define _SQLITE_OS_C_ 1
 #include "sqliteInt.h"
 #undef _SQLITE_OS_C_
 
+/*
+** If we compile with the SQLITE_TEST macro set, then the following block
+** of code will give us the ability to simulate a disk I/O error.  This
+** is used for testing the I/O recovery logic.
+*/
+#if defined(SQLITE_TEST)
+int sqlite3_io_error_hit = 0;            /* Total number of I/O Errors */
+int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */
+int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */
+int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */
+int sqlite3_io_error_benign = 0;         /* True if errors are benign */
+int sqlite3_diskfull_pending = 0;
+int sqlite3_diskfull = 0;
+#endif /* defined(SQLITE_TEST) */
+
+/*
+** When testing, also keep a count of the number of open files.
+*/
+#if defined(SQLITE_TEST)
+int sqlite3_open_file_count = 0;
+#endif /* defined(SQLITE_TEST) */
+
 /*
 ** The default SQLite sqlite3_vfs implementations do not allocate
 ** memory (actually, os_unix.c allocates a small amount of memory
 ** from within OsOpen()), but some third-party implementations may.
 ** So we test the effects of a malloc() failing and the sqlite3OsXXX()
 ** function returning SQLITE_IOERR_NOMEM using the DO_OS_MALLOC_TEST macro.
 **
-** The following functions are instrumented for malloc() failure 
+** The following functions are instrumented for malloc() failure
 ** testing:
 **
 **     sqlite3OsRead()
 **     sqlite3OsWrite()
 **     sqlite3OsSync()
@@ -108,12 +130,12 @@
 */
 int sqlite3OsFileControl(sqlite3_file *id, int op, void *pArg){
 #ifdef SQLITE_TEST
   if( op!=SQLITE_FCNTL_COMMIT_PHASETWO ){
     /* Faults are not injected into COMMIT_PHASETWO because, assuming SQLite
-    ** is using a regular VFS, it is called after the corresponding 
-    ** transaction has been committed. Injecting a fault at this point 
+    ** is using a regular VFS, it is called after the corresponding
+    ** transaction has been committed. Injecting a fault at this point
     ** confuses the test scripts - the COMMIT comand returns SQLITE_NOMEM
     ** but the transaction is committed anyway.
     **
     ** The core must call OsFileControl() though, not OsFileControlHint(),
     ** as if a custom VFS (e.g. zipvfs) returns an error here, it probably
@@ -178,14 +200,14 @@
 /*
 ** The next group of routines are convenience wrappers around the
 ** VFS methods.
 */
 int sqlite3OsOpen(
-  sqlite3_vfs *pVfs, 
-  const char *zPath, 
-  sqlite3_file *pFile, 
-  int flags, 
+  sqlite3_vfs *pVfs,
+  const char *zPath,
+  sqlite3_file *pFile,
+  int flags,
   int *pFlagsOut
 ){
   int rc;
   int openFlags;
   DO_OS_MALLOC_TEST(0);
@@ -206,22 +228,22 @@
   DO_OS_MALLOC_TEST(0);
   assert( dirSync==0 || dirSync==1 );
   return pVfs->xDelete(pVfs, zPath, dirSync);
 }
 int sqlite3OsAccess(
-  sqlite3_vfs *pVfs, 
-  const char *zPath, 
-  int flags, 
+  sqlite3_vfs *pVfs,
+  const char *zPath,
+  int flags,
   int *pResOut
 ){
   DO_OS_MALLOC_TEST(0);
   return pVfs->xAccess(pVfs, zPath, flags, pResOut);
 }
 int sqlite3OsFullPathname(
-  sqlite3_vfs *pVfs, 
-  const char *zPath, 
-  int nPathOut, 
+  sqlite3_vfs *pVfs,
+  const char *zPath,
+  int nPathOut,
   char *zPathOut
 ){
   DO_OS_MALLOC_TEST(0);
   zPathOut[0] = 0;
   return pVfs->xFullPathname(pVfs, zPath, nPathOut, zPathOut);
@@ -263,13 +285,13 @@
   }
   return rc;
 }
 
 int sqlite3OsOpenMalloc(
-  sqlite3_vfs *pVfs, 
-  const char *zFile, 
-  sqlite3_file **ppFile, 
+  sqlite3_vfs *pVfs,
+  const char *zFile,
+  sqlite3_file **ppFile,
   int flags,
   int *pOutFlags
 ){
   int rc = SQLITE_NOMEM;
   sqlite3_file *pFile;

Index: src/os_common.h
==================================================================
--- src/os_common.h
+++ src/os_common.h
@@ -33,12 +33,12 @@
 ** Macros for performance tracing.  Normally turned off.  Only works
 ** on i486 hardware.
 */
 #ifdef SQLITE_PERFORMANCE_TRACE
 
-/* 
-** hwtime.h contains inline assembler code for implementing 
+/*
+** hwtime.h contains inline assembler code for implementing
 ** high-performance timing routines.
 */
 #include "hwtime.h"
 
 static sqlite_uint64 g_start;
@@ -55,18 +55,18 @@
 /*
 ** If we compile with the SQLITE_TEST macro set, then the following block
 ** of code will give us the ability to simulate a disk I/O error.  This
 ** is used for testing the I/O recovery logic.
 */
-#ifdef SQLITE_TEST
-int sqlite3_io_error_hit = 0;            /* Total number of I/O Errors */
-int sqlite3_io_error_hardhit = 0;        /* Number of non-benign errors */
-int sqlite3_io_error_pending = 0;        /* Count down to first I/O error */
-int sqlite3_io_error_persist = 0;        /* True if I/O errors persist */
-int sqlite3_io_error_benign = 0;         /* True if errors are benign */
-int sqlite3_diskfull_pending = 0;
-int sqlite3_diskfull = 0;
+#if defined(SQLITE_TEST)
+extern int sqlite3_io_error_hit;
+extern int sqlite3_io_error_hardhit;
+extern int sqlite3_io_error_pending;
+extern int sqlite3_io_error_persist;
+extern int sqlite3_io_error_benign;
+extern int sqlite3_diskfull_pending;
+extern int sqlite3_diskfull;
 #define SimulateIOErrorBenign(X) sqlite3_io_error_benign=(X)
 #define SimulateIOError(CODE)  \
   if( (sqlite3_io_error_persist && sqlite3_io_error_hit) \
        || sqlite3_io_error_pending-- == 1 )  \
               { local_ioerr(); CODE; }
@@ -88,18 +88,18 @@
    }
 #else
 #define SimulateIOErrorBenign(X)
 #define SimulateIOError(A)
 #define SimulateDiskfullError(A)
-#endif
+#endif /* defined(SQLITE_TEST) */
 
 /*
 ** When testing, keep a count of the number of open files.
 */
-#ifdef SQLITE_TEST
-int sqlite3_open_file_count = 0;
+#if defined(SQLITE_TEST)
+extern int sqlite3_open_file_count;
 #define OpenCounter(X)  sqlite3_open_file_count+=(X)
 #else
 #define OpenCounter(X)
-#endif
+#endif /* defined(SQLITE_TEST) */
 
 #endif /* !defined(_OS_COMMON_H_) */

Index: src/shell.c
==================================================================
--- src/shell.c
+++ src/shell.c
@@ -590,10 +590,11 @@
 */
 typedef struct ShellState ShellState;
 struct ShellState {
   sqlite3 *db;           /* The database */
   int echoOn;            /* True to echo input commands */
+  int autoExplain;       /* Automatically turn on .explain mode */
   int autoEQP;           /* Run EXPLAIN QUERY PLAN prior to seach SQL stmt */
   int statsOn;           /* True to display memory stats before each finalize */
   int scanstatsOn;       /* True to display scan stats before each finalize */
   int countChanges;      /* True to display change counts */
   int backslashOn;       /* Resolve C-style \x escapes in SQL input text */
@@ -601,10 +602,12 @@
   int cnt;               /* Number of records displayed so far */
   FILE *out;             /* Write results here */
   FILE *traceOut;        /* Output for sqlite3_trace() */
   int nErr;              /* Number of errors seen */
   int mode;              /* An output mode setting */
+  int cMode;             /* temporary output mode for the current query */
+  int normalMode;        /* Output mode before ".explain on" */
   int writableSchema;    /* True if PRAGMA writable_schema=ON */
   int showHeader;        /* True to show column names in List or Column mode */
   unsigned shellFlgs;    /* Various flags */
   char *zDestTable;      /* Name of destination table when MODE_Insert */
   char colSeparator[20]; /* Column separator character for several modes */
@@ -611,11 +614,10 @@
   char rowSeparator[20]; /* Row separator character for MODE_Ascii */
   int colWidth[100];     /* Requested width of each column when in column mode*/
   int actualWidth[100];  /* Actual width of each column */
   char nullValue[20];    /* The text to print when a NULL comes back from
                          ** the database */
-  SavedModeInfo normalMode;/* Holds the mode just before .explain ON */
   char outfile[FILENAME_MAX]; /* Filename for *out */
   const char *zDbFilename;    /* name of the database file */
   char *zFreeOnClose;         /* Filename to free when closing */
   const char *zVfs;           /* Name of VFS to use */
   sqlite3_stmt *pStmt;   /* Current statement if any. */
@@ -880,11 +882,11 @@
   int *aiType      /* Column types */
 ){
   int i;
   ShellState *p = (ShellState*)pArg;
 
-  switch( p->mode ){
+  switch( p->cMode ){
     case MODE_Line: {
       int w = 5;
       if( azArg==0 ) break;
       for(i=0; i<nArg; i++){
         int len = strlen30(azCol[i] ? azCol[i] : "");
@@ -897,15 +899,28 @@
       }
       break;
     }
     case MODE_Explain:
     case MODE_Column: {
+      static const int aExplainWidths[] = {4, 13, 4, 4, 4, 13, 2, 13};
+      const int *colWidth;
+      int showHdr;
+      char *rowSep;
+      if( p->cMode==MODE_Column ){
+        colWidth = p->colWidth;
+        showHdr = p->showHeader;
+        rowSep = p->rowSeparator;
+      }else{
+        colWidth = aExplainWidths;
+        showHdr = 1;
+        rowSep = SEP_Row;
+      }
       if( p->cnt++==0 ){
         for(i=0; i<nArg; i++){
           int w, n;
           if( i<ArraySize(p->colWidth) ){
-            w = p->colWidth[i];
+            w = colWidth[i];
           }else{
             w = 0;
           }
           if( w==0 ){
             w = strlen30(azCol[i] ? azCol[i] : "");
@@ -914,21 +929,21 @@
             if( w<n ) w = n;
           }
           if( i<ArraySize(p->actualWidth) ){
             p->actualWidth[i] = w;
           }
-          if( p->showHeader ){
+          if( showHdr ){
             if( w<0 ){
               utf8_printf(p->out,"%*.*s%s",-w,-w,azCol[i],
-                      i==nArg-1 ? p->rowSeparator : "  ");
+                      i==nArg-1 ? rowSep : "  ");
             }else{
               utf8_printf(p->out,"%-*.*s%s",w,w,azCol[i],
-                      i==nArg-1 ? p->rowSeparator : "  ");
+                      i==nArg-1 ? rowSep : "  ");
             }
           }
         }
-        if( p->showHeader ){
+        if( showHdr ){
           for(i=0; i<nArg; i++){
             int w;
             if( i<ArraySize(p->actualWidth) ){
                w = p->actualWidth[i];
                if( w<0 ) w = -w;
@@ -936,11 +951,11 @@
                w = 10;
             }
             utf8_printf(p->out,"%-*.*s%s",w,w,
                    "----------------------------------------------------------"
                    "----------------------------------------------------------",
-                    i==nArg-1 ? p->rowSeparator : "  ");
+                    i==nArg-1 ? rowSep : "  ");
           }
         }
       }
       if( azArg==0 ) break;
       for(i=0; i<nArg; i++){
@@ -948,11 +963,11 @@
         if( i<ArraySize(p->actualWidth) ){
            w = p->actualWidth[i];
         }else{
            w = 10;
         }
-        if( p->mode==MODE_Explain && azArg[i] && strlen30(azArg[i])>w ){
+        if( p->cMode==MODE_Explain && azArg[i] && strlen30(azArg[i])>w ){
           w = strlen30(azArg[i]);
         }
         if( i==1 && p->aiIndent && p->pStmt ){
           if( p->iIndent<p->nIndent ){
             utf8_printf(p->out, "%*.s", p->aiIndent[p->iIndent], "");
@@ -960,15 +975,15 @@
           p->iIndent++;
         }
         if( w<0 ){
           utf8_printf(p->out,"%*.*s%s",-w,-w,
               azArg[i] ? azArg[i] : p->nullValue,
-              i==nArg-1 ? p->rowSeparator : "  ");
+              i==nArg-1 ? rowSep : "  ");
         }else{
           utf8_printf(p->out,"%-*.*s%s",w,w,
               azArg[i] ? azArg[i] : p->nullValue,
-              i==nArg-1 ? p->rowSeparator : "  ");
+              i==nArg-1 ? rowSep : "  ");
         }
       }
       break;
     }
     case MODE_Semi:
@@ -984,11 +999,11 @@
         char *z = azArg[i];
         if( z==0 ) z = p->nullValue;
         utf8_printf(p->out, "%s", z);
         if( i<nArg-1 ){
           utf8_printf(p->out, "%s", p->colSeparator);
-        }else if( p->mode==MODE_Semi ){
+        }else if( p->cMode==MODE_Semi ){
           utf8_printf(p->out, ";%s", p->rowSeparator);
         }else{
           utf8_printf(p->out, "%s", p->rowSeparator);
         }
       }
@@ -1489,14 +1504,21 @@
                             "Rewind", 0 };
   const char *azGoto[] = { "Goto", 0 };
 
   /* Try to figure out if this is really an EXPLAIN statement. If this
   ** cannot be verified, return early.  */
+  if( sqlite3_column_count(pSql)!=8 ){
+    p->cMode = p->mode;
+    return;
+  }
   zSql = sqlite3_sql(pSql);
   if( zSql==0 ) return;
   for(z=zSql; *z==' ' || *z=='\t' || *z=='\n' || *z=='\f' || *z=='\r'; z++);
-  if( sqlite3_strnicmp(z, "explain", 7) ) return;
+  if( sqlite3_strnicmp(z, "explain", 7) ){
+    p->cMode = p->mode;
+    return;
+  }
 
   for(iOp=0; SQLITE_ROW==sqlite3_step(pSql); iOp++){
     int i;
     int iAddr = sqlite3_column_int(pSql, 0);
     const char *zOp = (const char*)sqlite3_column_text(pSql, 1);
@@ -1509,10 +1531,24 @@
     int p2 = sqlite3_column_int(pSql, 3);
     int p2op = (p2 + (iOp-iAddr));
 
     /* Grow the p->aiIndent array as required */
     if( iOp>=nAlloc ){
+      if( iOp==0 ){
+        /* Do further verfication that this is explain output.  Abort if
+        ** it is not */
+        static const char *explainCols[] = {
+           "addr", "opcode", "p1", "p2", "p3", "p4", "p5", "comment" };
+        int jj;
+        for(jj=0; jj<ArraySize(explainCols); jj++){
+          if( strcmp(sqlite3_column_name(pSql,jj),explainCols[jj])!=0 ){
+            p->cMode = p->mode;
+            sqlite3_reset(pSql);
+            return;
+          }
+        }
+      }
       nAlloc += 100;
       p->aiIndent = (int*)sqlite3_realloc64(p->aiIndent, nAlloc*sizeof(int));
       abYield = (int*)sqlite3_realloc64(abYield, nAlloc*sizeof(int));
     }
     abYield[iOp] = str_in_array(zOp, azYield);
@@ -1612,14 +1648,24 @@
         }
         sqlite3_finalize(pExplain);
         sqlite3_free(zEQP);
       }
 
-      /* If the shell is currently in ".explain" mode, gather the extra
-      ** data required to add indents to the output.*/
-      if( pArg && pArg->mode==MODE_Explain ){
-        explain_data_prepare(pArg, pStmt);
+      if( pArg ){
+        pArg->cMode = pArg->mode;
+        if( pArg->autoExplain
+         && sqlite3_column_count(pStmt)==8
+         && sqlite3_strlike("%EXPLAIN%", sqlite3_sql(pStmt),0)==0
+        ){
+          pArg->cMode = MODE_Explain;
+        }
+      
+        /* If the shell is currently in ".explain" mode, gather the extra
+        ** data required to add indents to the output.*/
+        if( pArg->cMode==MODE_Explain ){
+          explain_data_prepare(pArg, pStmt);
+        }
       }
 
       /* perform the first step.  this will tell us if we
       ** have a result set or not and how wide it is.
       */
@@ -1645,11 +1691,11 @@
             }
             do{
               /* extract the data and data types */
               for(i=0; i<nCol; i++){
                 aiTypes[i] = x = sqlite3_column_type(pStmt, i);
-                if( x==SQLITE_BLOB && pArg && pArg->mode==MODE_Insert ){
+                if( x==SQLITE_BLOB && pArg && pArg->cMode==MODE_Insert ){
                   azVals[i] = "";
                 }else{
                   azVals[i] = (char*)sqlite3_column_text(pStmt, i);
                 }
                 if( !azVals[i] && (aiTypes[i]!=SQLITE_NULL) ){
@@ -1865,12 +1911,11 @@
   "                         If TABLE specified, only dump tables matching\n"
   "                         LIKE pattern TABLE.\n"
   ".echo on|off           Turn command echo on or off\n"
   ".eqp on|off            Enable or disable automatic EXPLAIN QUERY PLAN\n"
   ".exit                  Exit this program\n"
-  ".explain ?on|off?      Turn output mode suitable for EXPLAIN on or off.\n"
-  "                         With no args, it turns EXPLAIN on.\n"
+  ".explain ?on|off|auto? Turn EXPLAIN output mode on or off or to automatic\n"
   ".fullschema            Show schema and the content of sqlite_stat tables\n"
   ".headers on|off        Turn display of headers on or off\n"
   ".help                  Show this message\n"
   ".import FILE TABLE     Import data from FILE into TABLE\n"
   ".indexes ?TABLE?       Show names of all indexes\n"
@@ -2853,11 +2898,11 @@
     ShellState data;
     char *zErrMsg = 0;
     open_db(p, 0);
     memcpy(&data, p, sizeof(data));
     data.showHeader = 1;
-    data.mode = MODE_Column;
+    data.cMode = data.mode = MODE_Column;
     data.colWidth[0] = 3;
     data.colWidth[1] = 15;
     data.colWidth[2] = 58;
     data.cnt = 0;
     sqlite3_exec(p->db, "PRAGMA database_list; ", callback, &data, &zErrMsg);
@@ -2948,41 +2993,28 @@
     if( nArg>1 && (rc = (int)integerValue(azArg[1]))!=0 ) exit(rc);
     rc = 2;
   }else
 
   if( c=='e' && strncmp(azArg[0], "explain", n)==0 ){
-    int val = nArg>=2 ? booleanValue(azArg[1]) : 1;
-    if(val == 1) {
-      if(!p->normalMode.valid) {
-        p->normalMode.valid = 1;
-        p->normalMode.mode = p->mode;
-        p->normalMode.showHeader = p->showHeader;
-        memcpy(p->normalMode.colWidth,p->colWidth,sizeof(p->colWidth));
-      }
-      /* We could put this code under the !p->explainValid
-      ** condition so that it does not execute if we are already in
-      ** explain mode. However, always executing it allows us an easy
-      ** was to reset to explain mode in case the user previously
-      ** did an .explain followed by a .width, .mode or .header
-      ** command.
-      */
+    int val = 1;
+    if( nArg>=2 ){
+      if( strcmp(azArg[1],"auto")==0 ){
+        val = 99;
+      }else{
+        val =  booleanValue(azArg[1]);
+      }
+    }
+    if( val==1 && p->mode!=MODE_Explain ){
+      p->normalMode = p->mode;
       p->mode = MODE_Explain;
-      p->showHeader = 1;
-      memset(p->colWidth,0,sizeof(p->colWidth));
-      p->colWidth[0] = 4;                  /* addr */
-      p->colWidth[1] = 13;                 /* opcode */
-      p->colWidth[2] = 4;                  /* P1 */
-      p->colWidth[3] = 4;                  /* P2 */
-      p->colWidth[4] = 4;                  /* P3 */
-      p->colWidth[5] = 13;                 /* P4 */
-      p->colWidth[6] = 2;                  /* P5 */
-      p->colWidth[7] = 13;                  /* Comment */
-    }else if (p->normalMode.valid) {
-      p->normalMode.valid = 0;
-      p->mode = p->normalMode.mode;
-      p->showHeader = p->normalMode.showHeader;
-      memcpy(p->colWidth,p->normalMode.colWidth,sizeof(p->colWidth));
+      p->autoExplain = 0;
+    }else if( val==0 ){
+      if( p->mode==MODE_Explain ) p->mode = p->normalMode;
+      p->autoExplain = 0;
+    }else if( val==99 ){
+      if( p->mode==MODE_Explain ) p->mode = p->normalMode;
+      p->autoExplain = 1;
     }
   }else
 
   if( c=='f' && strncmp(azArg[0], "fullschema", n)==0 ){
     ShellState data;
@@ -2994,11 +3026,11 @@
       goto meta_command_exit;
     }
     open_db(p, 0);
     memcpy(&data, p, sizeof(data));
     data.showHeader = 0;
-    data.mode = MODE_Semi;
+    data.cMode = data.mode = MODE_Semi;
     rc = sqlite3_exec(p->db,
        "SELECT sql FROM"
        "  (SELECT sql sql, type type, tbl_name tbl_name, name name, rowid x"
        "     FROM sqlite_master UNION ALL"
        "   SELECT sql, type, tbl_name, name, rowid FROM sqlite_temp_master) "
@@ -3019,11 +3051,11 @@
       raw_printf(p->out, "/* No STAT tables available */\n");
     }else{
       raw_printf(p->out, "ANALYZE sqlite_master;\n");
       sqlite3_exec(p->db, "SELECT 'ANALYZE sqlite_master'",
                    callback, &data, &zErrMsg);
-      data.mode = MODE_Insert;
+      data.cMode = data.mode = MODE_Insert;
       data.zDestTable = "sqlite_stat1";
       shell_exec(p->db, "SELECT * FROM sqlite_stat1",
                  shell_callback, &data,&zErrMsg);
       data.zDestTable = "sqlite_stat3";
       shell_exec(p->db, "SELECT * FROM sqlite_stat3",
@@ -3251,11 +3283,11 @@
     ShellState data;
     char *zErrMsg = 0;
     open_db(p, 0);
     memcpy(&data, p, sizeof(data));
     data.showHeader = 0;
-    data.mode = MODE_List;
+    data.cMode = data.mode = MODE_List;
     if( nArg==1 ){
       rc = sqlite3_exec(p->db,
         "SELECT name FROM sqlite_master "
         "WHERE type='index' AND name NOT LIKE 'sqlite_%' "
         "UNION ALL "
@@ -3437,10 +3469,11 @@
     }else {
       raw_printf(stderr, "Error: mode should be one of: "
          "ascii column csv html insert line list tabs tcl\n");
       rc = 1;
     }
+    p->cMode = p->mode;
   }else
 
   if( c=='n' && strncmp(azArg[0], "nullvalue", n)==0 ){
     if( nArg==2 ){
       sqlite3_snprintf(sizeof(p->nullValue), p->nullValue,
@@ -3626,11 +3659,11 @@
     ShellState data;
     char *zErrMsg = 0;
     open_db(p, 0);
     memcpy(&data, p, sizeof(data));
     data.showHeader = 0;
-    data.mode = MODE_Semi;
+    data.cMode = data.mode = MODE_Semi;
     if( nArg==2 ){
       int i;
       for(i=0; azArg[1][i]; i++) azArg[1][i] = ToLower(azArg[1][i]);
       if( strcmp(azArg[1],"sqlite_master")==0 ){
         char *new_argv[2], *new_colv[2];
@@ -3774,11 +3807,12 @@
       rc = 1;
       goto meta_command_exit;
     }
     utf8_printf(p->out, "%12.12s: %s\n","echo", p->echoOn ? "on" : "off");
     utf8_printf(p->out, "%12.12s: %s\n","eqp", p->autoEQP ? "on" : "off");
-    utf8_printf(p->out,"%9.9s: %s\n","explain",p->normalMode.valid?"on":"off");
+    utf8_printf(p->out, "%12.12s: %s\n","explain",
+         p->mode==MODE_Explain ? "on" : p->autoExplain ? "auto" : "off");
     utf8_printf(p->out,"%12.12s: %s\n","headers", p->showHeader ? "on" : "off");
     utf8_printf(p->out, "%12.12s: %s\n","mode", modeDescr[p->mode]);
     utf8_printf(p->out, "%12.12s: ", "nullvalue");
       output_c_string(p->out, p->nullValue);
       raw_printf(p->out, "\n");
@@ -4573,11 +4607,12 @@
 /*
 ** Initialize the state information in data
 */
 static void main_init(ShellState *data) {
   memset(data, 0, sizeof(*data));
-  data->mode = MODE_List;
+  data->normalMode = data->cMode = data->mode = MODE_List;
+  data->autoExplain = 1;
   memcpy(data->colSeparator,SEP_Column, 2);
   memcpy(data->rowSeparator,SEP_Row, 2);
   data->showHeader = 0;
   data->shellFlgs = SHFLG_Lookaside;
   sqlite3_config(SQLITE_CONFIG_URI, 1);
@@ -4906,10 +4941,11 @@
     }else{
       utf8_printf(stderr,"%s: Error: unknown option: %s\n", Argv0, z);
       raw_printf(stderr,"Use -help for a list of options.\n");
       return 1;
     }
+    data.cMode = data.mode;
   }
 
   if( !readStdin ){
     /* Run all arguments that do not begin with '-' as if they were separate
     ** command-line inputs, except for the argToSkip argument which contains

Index: src/sqlite.h.in
==================================================================
--- src/sqlite.h.in
+++ src/sqlite.h.in
@@ -345,11 +345,11 @@
 ** subsequent statements are skipped.  ^If the 5th parameter to sqlite3_exec()
 ** is not NULL then any error message is written into memory obtained
 ** from [sqlite3_malloc()] and passed back through the 5th parameter.
 ** To avoid memory leaks, the application should invoke [sqlite3_free()]
 ** on error message strings returned through the 5th parameter of
-** of sqlite3_exec() after the error message string is no longer needed.
+** sqlite3_exec() after the error message string is no longer needed.
 ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors
 ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to
 ** NULL before returning.
 **
 ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()

Index: src/sqliteInt.h
==================================================================
--- src/sqliteInt.h
+++ src/sqliteInt.h
@@ -3108,10 +3108,11 @@
     int n;                                     /* A counter */
     int iCur;                                  /* A cursor number */
     SrcList *pSrcList;                         /* FROM clause */
     struct SrcCount *pSrcCount;                /* Counting column references */
     struct CCurHint *pCCurHint;                /* Used by codeCursorHint() */
+    int *aiCol;                                /* array of column indexes */
   } u;
 };
 
 /* Forward declarations */
 int sqlite3WalkExpr(Walker*, Expr*);
@@ -3177,10 +3178,17 @@
 int sqlite3CantopenError(int);
 #define SQLITE_CORRUPT_BKPT sqlite3CorruptError(__LINE__)
 #define SQLITE_MISUSE_BKPT sqlite3MisuseError(__LINE__)
 #define SQLITE_CANTOPEN_BKPT sqlite3CantopenError(__LINE__)
 
+/*
+** FTS3 and FTS4 both require virtual table support
+*/
+#if defined(SQLITE_OMIT_VIRTUALTABLE)
+# undef SQLITE_ENABLE_FTS3
+# undef SQLITE_ENABLE_FTS4
+#endif
 
 /*
 ** FTS4 is really an extension for FTS3.  It is enabled using the
 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also call
 ** the SQLITE_ENABLE_FTS4 macro to serve as an alias for SQLITE_ENABLE_FTS3.
@@ -3553,11 +3561,11 @@
     Parse*,Table*,Trigger*,int,int,int,i16,u8,u8,u8,int);
 void sqlite3GenerateRowIndexDelete(Parse*, Table*, int, int, int*, int);
 int sqlite3GenerateIndexKey(Parse*, Index*, int, int, int, int*,Index*,int);
 void sqlite3ResolvePartIdxLabel(Parse*,int);
 void sqlite3GenerateConstraintChecks(Parse*,Table*,int*,int,int,int,int,
-                                     u8,u8,int,int*);
+                                     u8,u8,int,int*,int*);
 void sqlite3CompleteInsertion(Parse*,Table*,int,int,int,int*,int,int,int);
 int sqlite3OpenTableAndIndices(Parse*, Table*, int, u8, int, u8*, int*, int*);
 void sqlite3BeginWriteOperation(Parse*, int, int);
 void sqlite3MultiWrite(Parse*);
 void sqlite3MayAbort(Parse*);
@@ -3772,11 +3780,10 @@
 int sqlite3AnalysisLoad(sqlite3*,int iDB);
 void sqlite3DeleteIndexSamples(sqlite3*,Index*);
 void sqlite3DefaultRowEst(Index*);
 void sqlite3RegisterLikeFunctions(sqlite3*, int);
 int sqlite3IsLikeFunction(sqlite3*,Expr*,int*,char*);
-void sqlite3MinimumFileFormat(Parse*, int, int);
 void sqlite3SchemaClear(void *);
 Schema *sqlite3SchemaGet(sqlite3 *, Btree *);
 int sqlite3SchemaToIndex(sqlite3 *db, Schema *);
 KeyInfo *sqlite3KeyInfoAlloc(sqlite3*,int,int);
 void sqlite3KeyInfoUnref(KeyInfo*);

Index: src/update.c
==================================================================
--- src/update.c
+++ src/update.c
@@ -570,11 +570,12 @@
     int bReplace = 0;     /* True if REPLACE conflict resolution might happen */
 
     /* Do constraint checks. */
     assert( regOldRowid>0 );
     sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
-        regNewRowid, regOldRowid, chngKey, onError, labelContinue, &bReplace);
+        regNewRowid, regOldRowid, chngKey, onError, labelContinue, &bReplace,
+        aXRef);
 
     /* Do FK constraint checks. */
     if( hasFK ){
       sqlite3FkCheck(pParse, pTab, regOldRowid, 0, aXRef, chngKey);
     }

Index: src/where.c
==================================================================
--- src/where.c
+++ src/where.c
@@ -3436,11 +3436,10 @@
 ** Return the cost of sorting nRow rows, assuming that the keys have 
 ** nOrderby columns and that the first nSorted columns are already in
 ** order.
 */
 static LogEst whereSortingCost(
-  WhereInfo *pWInfo,
   LogEst nRow,
   int nOrderBy,
   int nSorted
 ){
   /* TUNING: Estimated cost of a full external sort, where N is 
@@ -3458,18 +3457,10 @@
   ** below.  */
   LogEst rScale, rSortCost;
   assert( nOrderBy>0 && 66==sqlite3LogEst(100) );
   rScale = sqlite3LogEst((nOrderBy-nSorted)*100/nOrderBy) - 66;
   rSortCost = nRow + estLog(nRow) + rScale + 16;
-
-  /* TUNING: The cost of implementing DISTINCT using a B-TREE is
-  ** similar but with a larger constant of proportionality. 
-  ** Multiply by an additional factor of 3.0.  */
-  if( pWInfo->wctrlFlags & WHERE_WANT_DISTINCT ){
-    rSortCost += 16;
-  }
-
   return rSortCost;
 }
 
 /*
 ** Given the list of WhereLoop objects at pWInfo->pLoops, this routine
@@ -3599,11 +3590,11 @@
           revMask = pFrom->revLoop;
         }
         if( isOrdered>=0 && isOrdered<nOrderBy ){
           if( aSortCost[isOrdered]==0 ){
             aSortCost[isOrdered] = whereSortingCost(
-                pWInfo, nRowEst, nOrderBy, isOrdered
+                nRowEst, nOrderBy, isOrdered
             );
           }
           rCost = sqlite3LogEstAdd(rUnsorted, aSortCost[isOrdered]);
 
           WHERETRACE(0x002,

Index: test/alter3.test
==================================================================
--- test/alter3.test
+++ test/alter3.test
@@ -182,11 +182,11 @@
   }
 } {1 100 {} 2 300 {}}
 if {!$has_codec} {
   do_test alter3-3.3 {
     get_file_format
-  } {3}
+  } {4}
 }
 ifcapable schema_version {
   do_test alter3-3.4 {
     execsql {
       PRAGMA schema_version;
@@ -218,11 +218,11 @@
   }
 } {1 100 {hello world} 2 300 {hello world}}
 if {!$has_codec} {
   do_test alter3-4.3 {
     get_file_format
-  } {3}
+  } {4}
 }
 ifcapable schema_version {
   do_test alter3-4.4 {
     execsql {
       PRAGMA schema_version;
@@ -268,11 +268,11 @@
     } {31}
   }
   if {!$has_codec} {
     do_test alter3-5.5 {
       list [get_file_format test2.db] [get_file_format]
-    } {2 3}
+    } {4 4}
   }
   do_test alter3-5.6 {
     execsql {
       ALTER TABLE aux.t1 ADD COLUMN d DEFAULT 1000;
       SELECT sql FROM aux.sqlite_master;
@@ -345,23 +345,23 @@
       execsql {
         CREATE TABLE abc(a, b, c);
         ALTER TABLE abc ADD d DEFAULT NULL;
       }
       get_file_format
-    } {2}
+    } {4}
     do_test alter3-7.3 {
       execsql {
         ALTER TABLE abc ADD e DEFAULT 10;
       }
       get_file_format
-    } {3}
+    } {4}
     do_test alter3-7.4 {
       execsql {
         ALTER TABLE abc ADD f DEFAULT NULL;
       }
       get_file_format
-    } {3}
+    } {4}
     do_test alter3-7.5 {
       execsql {
         VACUUM;
       }
       get_file_format

Index: test/check.test
==================================================================
--- test/check.test
+++ test/check.test
@@ -456,7 +456,27 @@
 #
 do_execsql_test 8.1 {
   CREATE TABLE t810(a, CHECK( main.t810.a>0 ));
   CREATE TABLE t811(b, CHECK( xyzzy.t811.b BETWEEN 5 AND 10 ));
 } {}
+
+# Make sure check constraints involving the ROWID are not ignored
+#
+do_execsql_test 9.1 {
+  CREATE TABLE t1(
+    a INTEGER PRIMARY KEY,
+    b INTEGER NOT NULL CONSTRAINT 'b-check' CHECK( b>a ),
+    c INTEGER NOT NULL CONSTRAINT 'c-check' CHECK( c>rowid*2 ),
+    d INTEGER NOT NULL CONSTRAINT 'd-check' CHECK( d BETWEEN b AND c )
+  );
+  INSERT INTO t1(a,b,c,d) VALUES(1,2,4,3),(2,4,6,5),(3,10,30,20);
+} {}
+do_catchsql_test 9.2 {
+  UPDATE t1 SET b=0 WHERE a=1;
+} {1 {CHECK constraint failed: b-check}}
+do_catchsql_test 9.3 {
+  UPDATE t1 SET c=a*2 WHERE a=1;
+} {1 {CHECK constraint failed: c-check}}
+
+
 
 finish_test

Index: tool/mkautoconfamal.sh
==================================================================
--- tool/mkautoconfamal.sh
+++ tool/mkautoconfamal.sh
@@ -20,20 +20,31 @@
 set -e
 set -u
 
 TMPSPACE=./mkpkg_tmp_dir
 VERSION=`cat $TOP/VERSION`
-
-# Set global variable $ARTIFACT to the "3xxyyzz" string incorporated 
-# into artifact filenames. And $VERSION2 to the "3.x.y[.z]" form.
-xx=`echo $VERSION|sed 's/3\.\([0-9]*\)\..*/\1/'`
-yy=`echo $VERSION|sed 's/3\.[^.]*\.\([0-9]*\).*/\1/'`
-zz=0
-set +e
-  zz=`echo $VERSION|sed 's/3\.[^.]*\.[^.]*\.\([0-9]*\).*/\1/'|grep -v '\.'`
-set -e
-ARTIFACT=`printf "3%.2d%.2d%.2d" $xx $yy $zz`
+HASH=`sed 's/^\(..........\).*/\1/' $TOP/manifest.uuid`
+DATETIME=`grep '^D' $TOP/manifest | sed -e 's/[^0-9]//g' -e 's/\(............\).*/\1/'`
+
+# If this script is given an argument of --snapshot, then generate a
+# snapshot tarball named for the current checkout SHA1 hash, rather than
+# the version number.
+#
+if test "$#" -ge 1 -a x$1 != x--snapshot
+then
+  # Set global variable $ARTIFACT to the "3xxyyzz" string incorporated 
+  # into artifact filenames. And $VERSION2 to the "3.x.y[.z]" form.
+  xx=`echo $VERSION|sed 's/3\.\([0-9]*\)\..*/\1/'`
+  yy=`echo $VERSION|sed 's/3\.[^.]*\.\([0-9]*\).*/\1/'`
+  zz=0
+  set +e
+    zz=`echo $VERSION|sed 's/3\.[^.]*\.[^.]*\.\([0-9]*\).*/\1/'|grep -v '\.'`
+  set -e
+  TARBALLNAME=`printf "sqlite-autoconf-3%.2d%.2d%.2d" $xx $yy $zz`
+else
+  TARBALLNAME=sqlite-snapshot-$DATETIME
+fi
 
 rm -rf $TMPSPACE
 cp -R $TOP/autoconf       $TMPSPACE
 cp sqlite3.c              $TMPSPACE
 cp sqlite3.h              $TMPSPACE
@@ -71,8 +82,10 @@
 rm -rf autom4te.cache
 
 cd ../
 ./configure && make dist
 tar -xzf sqlite-$VERSION.tar.gz
-mv sqlite-$VERSION sqlite-autoconf-$ARTIFACT
-tar -czf sqlite-autoconf-$ARTIFACT.tar.gz sqlite-autoconf-$ARTIFACT
-mv sqlite-autoconf-$ARTIFACT.tar.gz ..
+mv sqlite-$VERSION $TARBALLNAME
+tar -czf $TARBALLNAME.tar.gz $TARBALLNAME
+mv $TARBALLNAME.tar.gz ..
+cd ..
+ls -l $TARBALLNAME.tar.gz

Index: tool/mkvsix.tcl
==================================================================
--- tool/mkvsix.tcl
+++ tool/mkvsix.tcl
@@ -387,21 +387,21 @@
 set shortNames(WP80,2012) SQLite.WP80
 set shortNames(WP80,2013) SQLite.WP80.2013
 set shortNames(WP81,2013) SQLite.WP81
 set shortNames(Win32,2012) SQLite.Win32
 set shortNames(Win32,2013) SQLite.Win32.2013
-set shortNames(UAP,2015) SQLite.UAP.2015
+set shortNames(UWP,2015) SQLite.UWP.2015
 
 set displayNames(WinRT,2012) "SQLite for Windows Runtime"
 set displayNames(WinRT,2013) "SQLite for Windows Runtime"
 set displayNames(WinRT81,2013) "SQLite for Windows Runtime (Windows 8.1)"
 set displayNames(WP80,2012) "SQLite for Windows Phone"
 set displayNames(WP80,2013) "SQLite for Windows Phone"
 set displayNames(WP81,2013) "SQLite for Windows Phone 8.1"
 set displayNames(Win32,2012) "SQLite for Windows"
 set displayNames(Win32,2013) "SQLite for Windows"
-set displayNames(UAP,2015) "SQLite for Universal App Platform"
+set displayNames(UWP,2015) "SQLite for Universal Windows Platform"
 
 if {[string equal $packageFlavor WinRT]} then {
   set shortName $shortNames($packageFlavor,$vsVersion)
   set displayName $displayNames($packageFlavor,$vsVersion)
   set targetPlatformIdentifier Windows
@@ -453,19 +453,19 @@
   set maxPlatformVersion \
       [getMaxPlatformVersionXmlChunk $packageFlavor $vsVersion]
   set extraSdkPath "\\..\\$targetPlatformIdentifier"
   set extraFileListAttributes \
       [getExtraFileListXmlChunk $packageFlavor $vsVersion]
-} elseif {[string equal $packageFlavor UAP]} then {
+} elseif {[string equal $packageFlavor UWP]} then {
   if {$vsVersion ne "2015"} then {
     fail [appendArgs \
         "unsupported combination, package flavor " $packageFlavor \
         " is only supported with Visual Studio 2015"]
   }
   set shortName $shortNames($packageFlavor,$vsVersion)
   set displayName $displayNames($packageFlavor,$vsVersion)
-  set targetPlatformIdentifier UAP
+  set targetPlatformIdentifier UWP
   set targetPlatformVersion v0.8.0.0
   set minVsVersion [getMinVsVersionXmlChunk $vsVersion]
   set maxPlatformVersion \
       [getMaxPlatformVersionXmlChunk $packageFlavor $vsVersion]
   set extraSdkPath "\\..\\$targetPlatformIdentifier"
@@ -483,11 +483,11 @@
   set extraFileListAttributes \
       [getExtraFileListXmlChunk $packageFlavor $vsVersion]
 } else {
   fail [appendArgs \
       "unsupported package flavor, must be one of: " \
-      [list WinRT WinRT81 WP80 WP81 UAP Win32]]
+      [list WinRT WinRT81 WP80 WP81 UWP Win32]]
 }
 
 ###############################################################################
 
 #

Index: tool/warnings.sh
==================================================================
--- tool/warnings.sh
+++ tool/warnings.sh
@@ -3,13 +3,14 @@
 # Run this script in a directory with a working makefile to check for 
 # compiler warnings in SQLite.
 #
 rm -f sqlite3.c
 make sqlite3.c
-echo '********** No optimizations.  Includes FTS4 and RTREE *********'
+echo '********** No optimizations.  Includes FTS4/5, RTREE, JSON1 ***'
 gcc -c -Wshadow -Wall -Wextra -pedantic-errors -Wno-long-long -std=c89 \
       -ansi -DHAVE_STDINT_H -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_RTREE \
+      -DSQLITE_ENABLE_FTS5 -DSQLITE_ENABLE_JSON1 \
       sqlite3.c
 echo '********** Android configuration ******************************'
 gcc -c \
   -DHAVE_USLEEP=1 \
   -DSQLITE_HAVE_ISNAN \
@@ -33,9 +34,10 @@
   -Os sqlite3.c shell.c
 echo '********** No optimizations. ENABLE_STAT4. THREADSAFE=0 *******'
 gcc -c -Wshadow -Wall -Wextra -pedantic-errors -Wno-long-long -std=c89 \
       -ansi -DSQLITE_ENABLE_STAT4 -DSQLITE_THREADSAFE=0 \
       sqlite3.c
-echo '********** Optimized -O3.  Includes FTS4 and RTREE ************'
+echo '********** Optimized -O3.  Includes FTS4/5, RTREE, JSON1 ******'
 gcc -O3 -c -Wshadow -Wall -Wextra -pedantic-errors -Wno-long-long -std=c89 \
       -ansi -DHAVE_STDINT_H -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_RTREE \
+      -DSQLITE_ENABLE_FTS5 -DSQLITE_ENABLE_JSON1 \
       sqlite3.c