GCC 11 picks up an indentation problem as a warning, and so -Werror fails the build. This doesn't change the software from functioning but anything that causes a build with default options to fail is going to exclude it from software packaging systems.
$ make
gcc -g -I. -D_FILE_OFFSET_BITS=64 -Wall -Werror -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION -c sqlite3.c
sqlite3.c: In function ‘sqlite3DefaultRowEst’:
sqlite3.c:103150:3: error: this ‘if’ clause does not guard... [-Werror=misleading-indentation]
103150 | if( pIdx->pPartIdxWhere!=0 ) a[0] -= 10; assert( 10==sqlite3LogEst(2) );
| ^~
In file included from sqlite3.c:11616:
sqlite3.c:103150:45: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’
103150 | if( pIdx->pPartIdxWhere!=0 ) a[0] -= 10; assert( 10==sqlite3LogEst(2) );
| ^~~~~~
sqlite3.c:103151:3: error: this ‘if’ clause does not guard... [-Werror=misleading-indentation]
103151 | if( a[0]<33 ) a[0] = 33; assert( 33==sqlite3LogEst(10) );
| ^~
In file included from sqlite3.c:11616:
sqlite3.c:103151:45: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the ‘if’
103151 | if( a[0]<33 ) a[0] = 33; assert( 33==sqlite3LogEst(10) );
| ^~~~~~
cc1: all warnings being treated as errors
make: *** [Makefile:21: sqlite3.o] Error 1
$ gcc --version
gcc (GCC) 11.2.0
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