From b5d6db65b49528c45cdfa75200dc8013d332b0db Mon Sep 17 00:00:00 2001 From: shyouhei Date: Tue, 5 Jun 2018 06:50:20 +0000 Subject: `int isnan(double)` is a POSIXism - `isnan` is something relatively new. We need to provide one for those systems without it. However: - X/Open defines `int isnan(double)`. Note the `int`. - C99 defines `isnan(x)` to be a macro. - C++11 nukes them all, undefines all the "masking macro"s, and defines its own `bool isnan(double)`. Note the `bool`. - In C++, `int isnan(double)` and `bool isnan(double)` are incompatible. - So the mess. [Bug #14816][ruby-core:87364] further reading: https://developers.redhat.com/blog/2016/02/29/why-cstdlib-is-more-complicated-than-you-might-think/ git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@63571 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- include/ruby/missing.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include') diff --git a/include/ruby/missing.h b/include/ruby/missing.h index dc3fd502b5..2d3852c131 100644 --- a/include/ruby/missing.h +++ b/include/ruby/missing.h @@ -168,6 +168,8 @@ RUBY_EXTERN const union bytesequence4_or_float rb_nan; # include # endif # define isinf(x) (!finite(x) && !isnan(x)) +# elif __cplusplus >= 201103L +# include // it must include constexpr bool isinf(double); # else RUBY_EXTERN int isinf(double); # endif @@ -176,7 +178,11 @@ RUBY_EXTERN int isinf(double); #ifndef isnan # ifndef HAVE_ISNAN +# if __cplusplus >= 201103L +# include // it must include constexpr bool isnan(double); +# else RUBY_EXTERN int isnan(double); +# endif # endif #endif -- cgit v1.2.3