[PATCH] Better __ashlDI3, __ashrDI3 and __lshrDI3 functions, plus fixed __bswapsi2 function
Wed Nov 11 17:54:21 GMT 2020
On Wed, 11 Nov 2020, Jakub Jelinek via Gcc-patches wrote:
> So indeed, 0x80 << 24 is UB in C99/C11 and C++98, unclear in C89 and
> well defined in C++11 and later. I don't know if C2X is considering
> mandating two's complement and making it well defined like C++20 did.
C2x requires two's complement but that's only about representation; there
are no changes so far to what shifts are undefined.
Joseph S. Myers
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