Hi Jacek,
On Sat, 19 Dec 2020, Jacek Caban wrote:
Hi Martin,
On 18.12.2020 23:35, Martin Storsjo wrote:
This fixes building in PE mode with Clang in MSVC mode for both x86_64 and aarch64.
I'd expect x86_64 to be fixed by [1], we could do the same for aarch64.
Ah, I see - that explains it. Yeah I was a bit surprised to see that it didn't work as expected, as I presumed that you had tested building in MSVC mode.
The actual issue here seems to be that the signature of the intrinsic _InterlockedCompareExchange128 is slightly wrong. Clang 11 and older (and MSVC itself) doesn't mind, but I was testing with a fresh trunk version of clang, where it needs to match better. See https://godbolt.org/z/TWbMs8 for an example of the difference.
FWIW, I bisected the change in behaviour down to https://reviews.llvm.org/D77491.
In that case, the fix is simply to correct the signature of the declaration - sending a new patch for that instead.
// Martin