Remove const from _Atomic vars to make Clang happy

Clang does not allow using C11's atomic_load on const _Atomic variables.
Previously it just disabled use of C11 atomics if atomic_load didn't work on a
const _Atomic variable, but I think I'd prefer to have Clang use C11 atomics
for the added features (more explicit memory ordering) even if it means a few
instances of breaking const.

1 files changed, 3 insertions, 4 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3cb1e5f5..ac1133d4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -264,12 +264,11 @@ HAVE_C11_ALIGNAS)
 # Check if we have C11 _Atomic
 CHECK_C_SOURCE_COMPILES(
 "#include <stdatomic.h>
- const int _Atomic foo = ATOMIC_VAR_INIT(~0);
- int _Atomic bar = ATOMIC_VAR_INIT(0);
+ int _Atomic foo = ATOMIC_VAR_INIT(0);
  int main()
  {
-     atomic_fetch_add(&bar, 2);
-     return atomic_load(&foo);
+     atomic_fetch_add(&foo, 2);
+     return 0;
  }"
 HAVE_C11_ATOMIC)