Fix incorrect __builtin_constant_p test for c_align_to #18
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16 aligned to 8 or 16 will always be 16, so it is legal for __builtin_constant_p to return true here, and Clang indeed performs this optimization (while GCC does not). Adjust the argument to 8, in which case the result of the expression is not a known constant.
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Clang performs the calculations for the set of possible inputs (2 in this case), and if they compare equal, it will consider it a constant expression? Impressive. Thanks for the heads-up! Patch looks good! Thanks! |
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(Applied and pushed: adc78dde) |
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16 aligned to 8 or 16 will always be 16, so it is legal for __builtin_constant_p to return true here, and Clang indeed performs this optimization (while GCC does not).
Adjust the argument to 8, in which case the result of the expression is not a known constant.