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| author | ed <ed@FreeBSD.org> | 2012-01-05 12:05:48 +0000 |
|---|---|---|
| committer | ed <ed@FreeBSD.org> | 2012-01-05 12:05:48 +0000 |
| commit | 7b66fc748479f74f48351332bc661cc02bff0374 (patch) | |
| tree | 2c3837421c98d6a8c2bd6fe8421eedd7dc636b64 /include/complex.h | |
| parent | e3196d88828e276ddbcd21c347d95355ebbf9dac (diff) | |
| download | FreeBSD-src-7b66fc748479f74f48351332bc661cc02bff0374.zip FreeBSD-src-7b66fc748479f74f48351332bc661cc02bff0374.tar.gz | |
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
Diffstat (limited to 'include/complex.h')
| -rw-r--r-- | include/complex.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/include/complex.h b/include/complex.h index 4142304..395983f 100644 --- a/include/complex.h +++ b/include/complex.h @@ -29,11 +29,15 @@ #ifndef _COMPLEX_H #define _COMPLEX_H +#include <sys/cdefs.h> + #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 |
