mirror of https://git.tukaani.org/xz.git
77bc5bc6dd
Add a configure option --enable-unsafe-type-punning to get the old non-conforming memory access methods. It can be useful with old compilers or in some other less typical situations but shouldn't normally be used. Omit the packed struct trick for unaligned access. While it's best in some cases, this is simpler. If the memcpy trick doesn't work, one can request unsafe type punning from configure. Because CRC32/CRC64 code needs fast aligned reads, if no very safe way to do it is found, type punning is used as a fallback. This sucks but since it currently works in practice, it seems to be the least bad option. It's never needed with GCC >= 4.7 or Clang >= 3.6 since these support __builtin_assume_aligned and thus fast aligned access can be done with the memcpy trick. Other things: - Support GCC/Clang __builtin_bswapXX - Cleaner bswap fallback macros - Minor cleanups |
||
|---|---|---|
| .. | ||
| .gitignore | ||
| ax_check_capsicum.m4 | ||
| ax_pthread.m4 | ||
| getopt.m4 | ||
| posix-shell.m4 | ||
| tuklib_common.m4 | ||
| tuklib_cpucores.m4 | ||
| tuklib_integer.m4 | ||
| tuklib_mbstr.m4 | ||
| tuklib_physmem.m4 | ||
| tuklib_progname.m4 | ||