在 2018/12/31 2:56, Jacek Caban 写道: > Hello, > > We currently have a few checks for strict more in our math.h. It guards > some non-standard (or at least not present in requested standard > version) declarations. Some of those are pretty standard things like > M_PI, others are Windows-specific, like underscored versions of standard > functions. This causes some problems like [1] or [2] when one tries to > build with -std=c++... > > AFAIK, MSVC doesn't have a counterpart of strict standard more, so an
There is `/Za` but I haven't used it ever. > assumption that those declarations are always present is valid among > them. To mimic that, we could just remove __STRICT_ANSI__ checks. My > patch does not go so far. I used a safer and less controversial approach > and concentrated on C++ only. > > On Linux, g++ defines _GNU_SOURCE because libstdc++ relies on some > declarations that would be otherwise not be present (clang and libc++ > are the same AFAIK). I didn't check, but saw an info that it does > similar things on other platforms. That causes C++ to assume that things > like M_PI is present even if specified standard would mean otherwise. > The attached patch makes such assumption valid on mingw-w64 by > explicitly checking for C++ in places checking __STRICT_ANSI__. > Yes, I think this bad, but it is how GCC behaves. Is it really necessary to check for ｀__cplusplus`? It looks to me that the GNU C++ compiler i.e. `__GNUG__` should be checked instead. I grep'd over libstdc++ headers for `M_PI` and found no results. Which declaration was it that caused the failure? > Thanks, > Jacek > > [1] https://bugzilla.mozilla.org/show_bug.cgi?id=1390583#c106 > [2] https://bugzilla.mozilla.org/show_bug.cgi?id=1508316 > -- Best regards, LH_Mouse _______________________________________________ Mingw-w64-public mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mingw-w64-public
