Index: Makefile.msc
==================================================================
--- Makefile.msc
+++ Makefile.msc
@@ -8,10 +8,11 @@
 TOP = .
 
 # Set this non-0 to create and use the SQLite amalgamation file.
 #
 USE_AMALGAMATION = 1
+DEBUG=0
 
 # Version numbers and release number for the SQLite being compiled.
 #
 VERSION = 3.7
 VERSION_NUMBER = 3007007
@@ -39,22 +40,42 @@
 
 # Define -DNDEBUG to compile without debugging (i.e., for production usage)
 # Omitting the define will cause extra debugging code to be inserted and
 # includes extra comments when "EXPLAIN stmt" is used.
 #
+!IF $(DEBUG)==0
 TCC = $(TCC) -DNDEBUG
+!ENDIF
+
+!IF $(DEBUG)>1
+TCC = $(TCC) -DSQLITE_DEBUG
+!ENDIF
+
+!IF $(DEBUG)>3
+TCC = $(TCC) -DSQLITE_DEBUG_OS_TRACE=1
+!ENDIF
+
+!IF $(DEBUG)>4
+TCC = $(TCC) -DSQLITE_ENABLE_IOTRACE
+!ENDIF
 
 #
 # Prevent warnings about "insecure" runtime library functions being used.
 #
 TCC = $(TCC) -D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS
 
 #
-# Use native Win32 heap.
+# Use native Win32 heap instead of malloc/free?
 #
 TCC = $(TCC) -DSQLITE_WIN32_MALLOC=1
-# TCC = $(TCC) -DSQLITE_WIN32_MALLOC_VALIDATE=1
+
+#
+# Validate the heap on every call into the native Win32 heap subsystem?
+#
+!IF $(DEBUG)>2
+TCC = $(TCC) -DSQLITE_WIN32_MALLOC_VALIDATE=1
+!ENDIF
 
 # The locations of the Tcl header and library files.  Also, the library that
 # non-stubs enabled programs using Tcl must link against.  These variables
 # (TCLINCDIR, TCLLIBDIR, and LIBTCL) may be overridden via the environment
 # prior to running nmake in order to match the actual installed location and
@@ -127,10 +148,15 @@
 TCC = $(TCC) $(OPT_FEATURE_FLAGS)
 
 # Add in any optional parameters specified on the make commane line
 # ie.  make "OPTS=-DSQLITE_ENABLE_FOO=1 -DSQLITE_OMIT_FOO=1".
 TCC = $(TCC) $(OPTS)
+
+# Add debug information if enabled.
+!IF $(DEBUG)!=0
+TCC = $(TCC) -Zi -D_DEBUG
+!ENDIF
 
 # libtool compile/link
 LTCOMPILE = $(TCC) -Fo$@
 LTLIB = lib.exe
 LTLINK = $(TCC) -Fe$@
@@ -141,10 +167,14 @@
 # to deduce the binary type based on the object files.
 !IF "$(PLATFORM)"!=""
 LTLINKOPTS = /MACHINE:$(PLATFORM)
 LTLIBOPTS = /MACHINE:$(PLATFORM)
 !ENDIF
+
+!IF $(DEBUG)!=0
+LTLINKOPTS = $(LTLINKOPTS) /DEBUG
+!ENDIF
 
 # nawk compatible awk.
 NAWK = gawk.exe
 
 # You should not have to change anything below this line

Index: src/sqliteInt.h
==================================================================
--- src/sqliteInt.h
+++ src/sqliteInt.h
@@ -147,10 +147,15 @@
 ** specify which memory allocation subsystem to use.
 **
 **     SQLITE_SYSTEM_MALLOC          // Use normal system malloc()
 **     SQLITE_WIN32_MALLOC           // Use Win32 native heap API
 **     SQLITE_MEMDEBUG               // Debugging version of system malloc()
+**
+** On Windows, if the SQLITE_WIN32_MALLOC_VALIDATE macro is defined and the
+** assert() macro is enabled, each call into the Win32 native heap subsystem
+** will cause HeapValidate to be called.  If heap validation should fail, an
+** assertion will be triggered.
 **
 ** (Historical note:  There used to be several other options, but we've
 ** pared it down to just these two.)
 **
 ** If none of the above are defined, then set SQLITE_SYSTEM_MALLOC as