Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/tools/build/feature/test-sync-compare-and-swap.c b/tools/build/feature/test-sync-compare-and-swap.c
new file mode 100644
index 000000000..1e38d1930
--- /dev/null
+++ b/tools/build/feature/test-sync-compare-and-swap.c
@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdint.h>
+
+volatile uint64_t x;
+
+int main(int argc, char *argv[])
+{
+	uint64_t old, new = argc;
+
+	argv = argv;
+	do {
+		old = __sync_val_compare_and_swap(&x, 0, 0);
+	} while (!__sync_bool_compare_and_swap(&x, old, new));
+	return old == new;
+}