aaron.ballman added inline comments.
================ Comment at: clang/lib/Parse/ParseDeclCXX.cpp:874-876 + if (!getLangOpts().CPlusPlus) + Diag(Tok, diag::warn_cxx_static_assert_in_c) + << FixItHint::CreateReplacement(Tok.getLocation(), "_Static_assert"); ---------------- rsmith wrote: > I don't think this diagnostic is useful as-is: on Windows, including > `<assert.h>` doesn't help because it doesn't `#define static_assert`. And > people hitting this also can't switch to using `_Static_assert`, because MSVC > doesn't provide it, only `static_assert`. > > If we want to warn here, we could perhaps check whether `<assert.h>` has been > included, but getting that check correct across PCH / modules is not > straightforward. (If we knew what include guard the CRT's `assert.h` used (if > any), I guess we could check whether that's defined, but that'd be a bit of a > hack.) But I'm somewhat inclined to think we don't have a good way to > distinguish between the good cases and the bad ones, so we shouldn't warn. > Hopefully MS will fix their CRT at some point and we can stop providing this > compatibility hack entirely (or start warning on it by default). Are you sure they don't support `_Static_assert` yet? I seem to be able to use it fine: https://godbolt.org/z/vG47he That said, this does appear to be only available in newer versions of MSVC, so perhaps you're correct about the diagnostic being a bit unhelpful. My primary concern is that use of `static_assert` in C is a nonconforming extension and we default to `-fms-compatibility` on Windows when Clang is built by MSVC. So it's not difficult to accidentally run into this, but the only warning we give on it with `-Weverything -pedantic` is how it's not compatible with C++98. WDYT? CHANGES SINCE LAST ACTION https://reviews.llvm.org/D95396/new/ https://reviews.llvm.org/D95396 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
