diff options
Diffstat (limited to 'configure.ac')
| -rw-r--r-- | configure.ac | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/configure.ac b/configure.ac index 016e38fb599..83cd5d1d15e 100644 --- a/configure.ac +++ b/configure.ac @@ -415,6 +415,20 @@ if test "x$GCC_ATOMIC_BUILTINS_SUPPORTED" = x1; then fi AM_CONDITIONAL([GCC_ATOMIC_BUILTINS_SUPPORTED], [test x$GCC_ATOMIC_BUILTINS_SUPPORTED = x1]) +dnl Check if host supports 64-bit atomics +dnl note that lack of support usually results in link (not compile) error +AC_MSG_CHECKING(whether __sync_add_and_fetch_8 is supported) +AC_LINK_IFELSE([AC_LANG_SOURCE([[ +#include <stdint.h> +uint64_t v; +int main() { + return __sync_add_and_fetch(&v, (uint64_t)1); +}]])], GCC_64BIT_ATOMICS_SUPPORTED=yes, GCC_64BIT_ATOMICS_SUPPORTED=no) +if test "x$GCC_64BIT_ATOMICS_SUPPORTED" != xyes; then + DEFINES="$DEFINES -DMISSING_64BIT_ATOMICS" +fi +AC_MSG_RESULT($GCC_64BIT_ATOMICS_SUPPORTED) + dnl Check for Endianness AC_C_BIGENDIAN( little_endian=no, |