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fix: Detect platform word size based on SIZE_MAX
#125
fix: Detect platform word size based on SIZE_MAX
#125
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The native word size on a platform matches the size of `size_t` with a few rare exceptions like the x32 ABI on linux. Therefore we can derive a general cross platform value for `BASE64_WORDSIZE` based on `SIZE_MAX` which the C99 standard guarantees to be available and well defined. This fixes the misdection of x86/arm32 win32 as a 64bit platform. See also https://en.cppreference.com/w/c/types/limits
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#elif defined (__WORDSIZE) | ||
# define BASE64_WORDSIZE __WORDSIZE | ||
#elif defined (__SIZE_WIDTH__) | ||
# define BASE64_WORDSIZE __SIZE_WIDTH__ | ||
#elif SIZE_MAX == 0xffffffff |
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#elif SIZE_MAX == 0xffffffff | |
#elif SIZE_MAX == UINT32_MAX |
#elif defined (__WORDSIZE) | ||
# define BASE64_WORDSIZE __WORDSIZE | ||
#elif defined (__SIZE_WIDTH__) | ||
# define BASE64_WORDSIZE __SIZE_WIDTH__ | ||
#elif SIZE_MAX == 0xffffffff | ||
# define BASE64_WORDSIZE 32 | ||
#elif SIZE_MAX == 0xffffffffffffffff |
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#elif SIZE_MAX == 0xffffffffffffffff | |
#elif SIZE_MAX == UINT64_MAX |
@BurningEnlightenment, I did not write anything related to |
Merged with the fixes proposed by @mayeut. @BurningEnlightenment I slightly modified the commit title to add the issue number, and I modified the commit body to mark this issue and #123 as resolved. Hope you don't mind. |
@BurningEnlightenment I think it's a bit too late now to force-push to the master branch, so yes, please open a new PR. |
The native word size on a platform matches the size of
size_t
with a few rare exceptions like the x32 ABI on linux. Therefore we can derive a general cross platform value forBASE64_WORDSIZE
based onSIZE_MAX
which the C99 standard guarantees to be available and well defined.This fixes the misdection of x86/arm32 win32 as a 64bit platform, i.e. it is an alternative to #123
@mayeut I think this should also cover the
__WORDSIZE
and__SIZE_WIDTH__
cases. Can you verify this? If that indeed is the case I would like remove those branches, too.See also https://en.cppreference.com/w/c/types/limits