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| author | Thomas Petazzoni <thomas.petazzoni@free-electrons.com> | 2013-09-06 15:27:04 +0200 |
|---|---|---|
| committer | Lucas De Marchi <lucas.demarchi@intel.com> | 2013-09-06 11:06:19 -0300 |
| commit | dc8ed09f8f21d17ef9481001683d7edfdb308983 (patch) | |
| tree | 1a8bf2807d8a3aea3d0a9daf39b105a1d2603cee | |
| parent | 7e0385c47ae7c313a59de3ea431af7b5d18807d7 (diff) | |
| download | kmod-dc8ed09f8f21d17ef9481001683d7edfdb308983.tar.gz | |
Add configure check for _Static_assert()
Commit 8efede20ef ("Use _Static_assert") introduced the usage of
_Static_assert(). However, _Static_assert() is a fairly new thing,
since it was introduced only in gcc 4.6. In order to support older
compilers, this patch adds a configure.in test that checks whether
_Static_assert() is usable or not, and adjust the behavior of the
assert_cc() macro accordingly.
| -rw-r--r-- | configure.ac | 6 | ||||
| -rw-r--r-- | libkmod/macro.h | 5 |
2 files changed, 11 insertions, 0 deletions
diff --git a/configure.ac b/configure.ac index 40e54cf..a192c81 100644 --- a/configure.ac +++ b/configure.ac @@ -52,6 +52,12 @@ AC_CHECK_MEMBERS([struct stat.st_mtim], [], [], [#include <sys/stat.h>]) # Check kernel headers AC_CHECK_HEADERS_ONCE([linux/module.h]) +AC_MSG_CHECKING([whether _Static_assert() is supported]) +AC_COMPILE_IFELSE( + [AC_LANG_SOURCE([[_Static_assert(1, "Test");]])], + [AC_DEFINE([HAVE_STATIC_ASSERT], [1], [Define if _Static_assert() is available]) + AC_MSG_RESULT([yes])], + [AC_MSG_RESULT([no])]) ##################################################################### # --with- diff --git a/libkmod/macro.h b/libkmod/macro.h index c6ba855..10392a3 100644 --- a/libkmod/macro.h +++ b/libkmod/macro.h @@ -21,8 +21,13 @@ #include <stddef.h> +#if defined(HAVE_STATIC_ASSERT) #define assert_cc(expr) \ _Static_assert((expr), #expr) +#else +#define assert_cc(expr) \ + do { (void) sizeof(char [1 - 2*!(expr)]); } while(0) +#endif #if HAVE_TYPEOF #define check_types_match(expr1, expr2) \ |