On Wednesday 18 September 2024 12:05:44 Martin Storsjö wrote: > On Sun, 15 Sep 2024, Pali Rohár wrote: > > > When compiling any application with flags under gcc 7+ with flags > > -D__MINGW_INTRIN_INLINE -Wall -Wextra, it throws about 300 lines of > > preprocessor warnings for __INTRINSIC_PROLOG usage: > > warning: this use of "defined" may not be portable > > This isn't actually true for most installs of mingw-w64, so we probably > should change this message somewhat. > > --- > If the mingw-w64 headers are included in a way that doesn't mute warnings in > system headers, this header causes lots of warnings like: > warning: this use of "defined" may not be portable > --- > > That makes the scope of the patch clear.
That is good, I'm fine with it. > > It is caused by the fact that this macro __INTRINSIC_PROLOG uses > > non-portable Conditional inclusion (ISO WG14 N2176 (C17) 6.10.1/4). > > > > Disable this gcc warning via localized GCC pragmas to prevent 300 lines of > > warnings for every application. > > --- > > mingw-w64-headers/include/psdk_inc/intrin-impl.h | 14 ++++++++++++++ > > 1 file changed, 14 insertions(+) > > > > diff --git a/mingw-w64-headers/include/psdk_inc/intrin-impl.h > > b/mingw-w64-headers/include/psdk_inc/intrin-impl.h > > index b30e0404ba88..06bbbfe4f7df 100644 > > --- a/mingw-w64-headers/include/psdk_inc/intrin-impl.h > > +++ b/mingw-w64-headers/include/psdk_inc/intrin-impl.h > > @@ -67,6 +67,16 @@ __INTRINSICS_USEINLINE > > #define __has_builtin(x) 0 > > #endif > > > > +/* > > + * Macro __INTRINSIC_PROLOG uses non-portable Conditional inclusion > > + * (ISO WG14 N2176 (C17) 6.10.1/4). Avoid gcc 7+ -Wexpansion-to-defined > > + * warning enabled by -W or -Wextra option. > > + */ > > +#if defined(__GNUC__) && __GNUC__ >= 7 > > +#pragma GCC diagnostic push > > +#pragma GCC diagnostic ignored "-Wexpansion-to-defined" > > +#endif > > FWIW, Clang also has got this warning, but Clang presents itself as GCC 4.2 > in these defines, so we could do something like this: > > #if defined(__GNUC__) && (__GNUC__ >= 7 || defined(__clang__)) > > If we don't care about exactly when Clang has learnt about this warning - I > think it has been supported longer than we care about here. A quick dig in > the code seems that it was renamed in Clang 3.9 in > https://github.com/llvm/llvm-project/commit/b5d539380a9b548f28ffa067067f90d3139ca767. > So that's more than long enough. > > Curiously, this warning isn't enabled in Clang with -Wall -Wextra, but it is > enabled by -pedantic. > > So I guess we could amend these #ifs to include this condition. > > // Martin Ok, feel free to adjust this check for clang. _______________________________________________ Mingw-w64-public mailing list Mingw-w64-public@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/mingw-w64-public
