49 lines
1.6 KiB
Diff
49 lines
1.6 KiB
Diff
From 01839b509c1bb914337124ac3d1f644b05ef90d8 Mon Sep 17 00:00:00 2001
|
|
From: "Urabe, Shyouhei" <shyouhei@ruby-lang.org>
|
|
Date: Tue, 5 Jun 2018 10:26:06 +0900
|
|
Subject: [PATCH] C++11 is so bad it introduces a nightmare.
|
|
|
|
TL;DR see https://developers.redhat.com/blog/2016/02/29/why-cstdlib-is-more-complicated-than-you-might-think/
|
|
|
|
- `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
|
|
define its own `bool isnan(double)`. Note the `bool`.
|
|
- In C++, `int isnan(double)` and `bool isnan(double)` are
|
|
incompatible.
|
|
- So the mess.
|
|
|
|
Signed-off-by: Urabe, Shyouhei <shyouhei@ruby-lang.org>
|
|
---
|
|
include/ruby/missing.h | 6 ++++++
|
|
1 file changed, 6 insertions(+)
|
|
|
|
diff --git a/include/ruby/missing.h b/include/ruby/missing.h
|
|
index dc3fd502b5..8df917498e 100644
|
|
--- include/ruby/missing.h.orig
|
|
+++ include/ruby/missing.h
|
|
@@ -168,6 +168,8 @@ RUBY_EXTERN const union bytesequence4_or_float rb_nan;
|
|
# include <ieeefp.h>
|
|
# endif
|
|
# define isinf(x) (!finite(x) && !isnan(x))
|
|
+# elif __cplusplus >= 201103L
|
|
+# include <cmath> // 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 <cmath> // it must include constexpr bool isnan(double);
|
|
+# else
|
|
RUBY_EXTERN int isnan(double);
|
|
+# endif
|
|
# endif
|
|
#endif
|
|
|
|
--
|