С какой версией Valgrind у вас проблемы?
В Linux и MacOS одна сборка Valgrind может автоматически обнаруживать и выполнять правильные действия как для 32-, так и для 64-разрядных двоичных файлов.
Вот что я вижу на Mac OS X 10.6.7 (10J869)
:
$ echo "int main() { free(1); return 0; }" | gcc -xc - -g -o a.out
$ echo "int main() { free(1); return 0; }" | gcc -xc - -g -o a.out32 -m32
$ valgrind --version
valgrind-3.7.0.SVN
$ valgrind ./a.out
==46102== Memcheck, a memory error detector
==46102== Copyright (C) 2002-2010, and GNU GPL'd, by Julian Seward et al.
==46102== Using Valgrind-3.7.0.SVN and LibVEX; rerun with -h for copyright info
==46102== Command: ./a.out
==46102==
--46102-- ./a.out:
--46102-- dSYM directory is missing; consider using --dsymutil=yes
==46102== Invalid free() / delete / delete[] / realloc()
==46102== at 0x100010E9F: free (vg_replace_malloc.c:366)
==46102== by 0x100000F26: main (in ./a.out)
==46102== Address 0x1 is not stack'd, malloc'd or (recently) free'd
==46102==
==46102==
==46102== HEAP SUMMARY:
==46102== in use at exit: 88 bytes in 1 blocks
==46102== total heap usage: 1 allocs, 1 frees, 88 bytes allocated
==46102==
==46102== LEAK SUMMARY:
==46102== definitely lost: 0 bytes in 0 blocks
==46102== indirectly lost: 0 bytes in 0 blocks
==46102== possibly lost: 0 bytes in 0 blocks
==46102== still reachable: 0 bytes in 0 blocks
==46102== suppressed: 88 bytes in 1 blocks
==46102==
==46102== For counts of detected and suppressed errors, rerun with: -v
==46102== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)
$ valgrind ./a.out32
==46103== Memcheck, a memory error detector
==46103== Copyright (C) 2002-2010, and GNU GPL'd, by Julian Seward et al.
==46103== Using Valgrind-3.7.0.SVN and LibVEX; rerun with -h for copyright info
==46103== Command: ./a.out32
==46103==
--46103-- ./a.out32:
--46103-- dSYM directory is missing; consider using --dsymutil=yes
==46103== Invalid free() / delete / delete[] / realloc()
==46103== at 0xF7D8: free (vg_replace_malloc.c:366)
==46103== by 0x1F7B: main (in ./a.out32)
==46103== Address 0x1 is not stack'd, malloc'd or (recently) free'd
==46103==
==46103==
==46103== HEAP SUMMARY:
==46103== in use at exit: 320 bytes in 7 blocks
==46103== total heap usage: 7 allocs, 1 frees, 320 bytes allocated
==46103==
==46103== LEAK SUMMARY:
==46103== definitely lost: 0 bytes in 0 blocks
==46103== indirectly lost: 0 bytes in 0 blocks
==46103== possibly lost: 0 bytes in 0 blocks
==46103== still reachable: 260 bytes in 6 blocks
==46103== suppressed: 60 bytes in 1 blocks
==46103== Rerun with --leak-check=full to see details of leaked memory
==46103==
==46103== For counts of detected and suppressed errors, rerun with: -v
==46103== ERROR SUMMARY: 1 errors from 1 contexts (suppressed: 0 from 0)