diff options
| author | Thomas Huth <thuth@redhat.com> | 2018-09-26 17:48:50 +0200 |
|---|---|---|
| committer | Thomas Huth <thuth@redhat.com> | 2018-10-17 08:36:28 +0200 |
| commit | 97ff87c0ed020c2a4b931146e142d67abe852e22 (patch) | |
| tree | aa5c5de9ce476031ff56e27213f2cde13e769c09 /include | |
| parent | 957e8b34920a1404a1318b2e1ffa0726d40e0a9b (diff) | |
qemu/compiler: Wrap __attribute__((flatten)) in a macro
Older versions of Clang (before 3.5) and GCC (before 4.1) do not
support the "__attribute__((flatten))" yet. We don't care about
such old versions of GCC anymore, but since Clang 3.4 is still
used in EPEL for RHEL7 / CentOS 7, we should not use this attribute
directly but with a wrapper macro instead.
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/qemu/compiler.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h index bf47e7bee4..66f8c241dc 100644 --- a/include/qemu/compiler.h +++ b/include/qemu/compiler.h @@ -131,6 +131,21 @@ #define HAS_ASSUME_ALIGNED #endif +#ifndef __has_attribute +#define __has_attribute(x) 0 /* compatibility with older GCC */ +#endif + +/* + * GCC doesn't provide __has_attribute() until GCC 5, but we know all the GCC + * versions we support have the "flatten" attribute. Clang may not have the + * "flatten" attribute but always has __has_attribute() to check for it. + */ +#if __has_attribute(flatten) || !defined(__clang__) +# define QEMU_FLATTEN __attribute__((flatten)) +#else +# define QEMU_FLATTEN +#endif + /* Implement C11 _Generic via GCC builtins. Example: * * QEMU_GENERIC(x, (float, sinf), (long double, sinl), sin) (x) |