[ndebug=false])
AM_CONDITIONAL([NDEBUG], [test x$ndebug = xtrue])])
-dnl Checks for --enable-cache-time and defines CACHE_TIME if it is specified.
-AC_DEFUN([OVS_CHECK_CACHE_TIME],
- [AC_ARG_ENABLE(
- [cache-time],
- [AC_HELP_STRING([--enable-cache-time],
- [Override time caching default (for testing only)])],
- [case "${enableval}" in
- (yes) cache_time=1;;
- (no) cache_time=0;;
- (*) AC_MSG_ERROR([bad value ${enableval} for --enable-cache-time]) ;;
- esac
- AC_DEFINE_UNQUOTED([CACHE_TIME], [$cache_time],
- [Define to 1 to enable time caching, to 0 to disable time caching, or
- leave undefined to use the default (as one should
- ordinarily do).])])])
-
dnl Checks for ESX.
AC_DEFUN([OVS_CHECK_ESX],
[AC_CHECK_HEADER([vmware.h],
fi
fi])
+dnl OVS_CHECK_GCC4_ATOMICS
+dnl
+dnl Checks whether the compiler and linker support GCC 4.0+ atomic built-ins.
+dnl A compile-time only check is not enough because the compiler defers
+dnl unimplemented built-ins to libgcc, which sometimes also lacks
+dnl implementations.
+AC_DEFUN([OVS_CHECK_GCC4_ATOMICS],
+ [AC_CACHE_CHECK(
+ [whether $CC supports GCC 4.0+ atomic built-ins],
+ [ovs_cv_gcc4_atomics],
+ [AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM([[#include <stdlib.h>
+
+#define ovs_assert(expr) if (!(expr)) abort();
+#define TEST_ATOMIC_TYPE(TYPE) \
+ { \
+ TYPE x = 1; \
+ TYPE orig; \
+ \
+ __sync_synchronize(); \
+ ovs_assert(x == 1); \
+ \
+ __sync_synchronize(); \
+ x = 3; \
+ __sync_synchronize(); \
+ ovs_assert(x == 3); \
+ \
+ orig = __sync_fetch_and_add(&x, 1); \
+ ovs_assert(orig == 3); \
+ __sync_synchronize(); \
+ ovs_assert(x == 4); \
+ \
+ orig = __sync_fetch_and_sub(&x, 2); \
+ ovs_assert(orig == 4); \
+ __sync_synchronize(); \
+ ovs_assert(x == 2); \
+ \
+ orig = __sync_fetch_and_or(&x, 6); \
+ ovs_assert(orig == 2); \
+ __sync_synchronize(); \
+ ovs_assert(x == 6); \
+ \
+ orig = __sync_fetch_and_and(&x, 10); \
+ ovs_assert(orig == 6); \
+ __sync_synchronize(); \
+ ovs_assert(x == 2); \
+ \
+ orig = __sync_fetch_and_xor(&x, 10); \
+ ovs_assert(orig == 2); \
+ __sync_synchronize(); \
+ ovs_assert(x == 8); \
+ }]], [dnl
+TEST_ATOMIC_TYPE(char);
+TEST_ATOMIC_TYPE(unsigned char);
+TEST_ATOMIC_TYPE(signed char);
+TEST_ATOMIC_TYPE(short);
+TEST_ATOMIC_TYPE(unsigned short);
+TEST_ATOMIC_TYPE(int);
+TEST_ATOMIC_TYPE(unsigned int);
+TEST_ATOMIC_TYPE(long int);
+TEST_ATOMIC_TYPE(unsigned long int);
+TEST_ATOMIC_TYPE(long long int);
+TEST_ATOMIC_TYPE(unsigned long long int);
+])],
+ [ovs_cv_gcc4_atomics=yes],
+ [ovs_cv_gcc4_atomics=no])])
+ if test $ovs_cv_gcc4_atomics = yes; then
+ AC_DEFINE([HAVE_GCC4_ATOMICS], [1],
+ [Define to 1 if the C compiler and linker supports the GCC 4.0+
+ atomic built-ins.])
+ fi])
+
dnl OVS_CHECK_ATOMIC_ALWAYS_LOCK_FREE(SIZE)
dnl
dnl Checks __atomic_always_lock_free(SIZE, 0)