From f92d9d7d375049753865aa2a50428162f23c4a44 Mon Sep 17 00:00:00 2001 From: Ed Schouten Date: Thu, 5 Jan 2012 12:05:48 +0000 Subject: [PATCH] Make _Complex_I a proper float _Complex when using GCC 4.2. It turns out our GCC has quite an interesting bug: typeof(1.0fi) != float _Complex typeof((float _Complex)1.0fi) != float _Complex typeof((float _Complex)1.0i) == float _Complex In other words: if casting to an equal size, GCC seems to take a shortcut. By casting down from a double to a float, GCC doesn't take this shortcut, yielding the proper type. To prevent foot-shooting, add a _Static_assert() to guarantee that _Complex_I is always a float _Complex. I'm not going to MFC this part of the diff. MFC after: 2 weeks --- include/complex.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/include/complex.h b/include/complex.h index 414230472d2b..395983fab5c4 100644 --- a/include/complex.h +++ b/include/complex.h @@ -29,11 +29,15 @@ #ifndef _COMPLEX_H #define _COMPLEX_H +#include + #ifdef __GNUC__ #if __STDC_VERSION__ < 199901 #define _Complex __complex__ #endif -#define _Complex_I 1.0fi +#define _Complex_I ((float _Complex)1.0i) +_Static_assert(__generic(_Complex_I, float _Complex, 1, 0), + "_Complex_I must be of type float _Complex"); #endif #define complex _Complex