test for 32 bit atomic builtins was incorrectly testing for 64 bit atomics

noticed when going over a macppc clang build error reported by deraadt@

2 files changed, 2 insertions, 2 deletions

diff --git a/lib/mesa/configure b/lib/mesa/configure
index 693be0461..bbfe4636c 100755
--- a/lib/mesa/configure
+++ b/lib/mesa/configure
@@ -21122,7 +21122,7 @@ cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
 #include <stdint.h>
-uint64_t v;
+uint32_t v;
 int main() {
     return __sync_add_and_fetch(&v, (uint32_t)1);
 }
diff --git a/lib/mesa/configure.ac b/lib/mesa/configure.ac
index 53d8374ca..eaf24d4c7 100644
--- a/lib/mesa/configure.ac
+++ b/lib/mesa/configure.ac
@@ -522,7 +522,7 @@ dnl Check if host supports 32-bit atomics
 AC_MSG_CHECKING(whether __sync_add_and_fetch_4 is supported)
 AC_LINK_IFELSE([AC_LANG_SOURCE([[
 #include <stdint.h>
-uint64_t v;
+uint32_t v;
 int main() {
     return __sync_add_and_fetch(&v, (uint32_t)1);
 }]])], GCC_32BIT_ATOMICS_SUPPORTED=yes, GCC_32BIT_ATOMICS_SUPPORTED=no)