Index: compiler-rt/lib/builtins/ppc/atomic_lock_free.c
--- compiler-rt/lib/builtins/ppc/atomic_lock_free.c.orig
+++ compiler-rt/lib/builtins/ppc/atomic_lock_free.c
@@ -0,0 +1,22 @@
+/* Public domain. */
+
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdlib.h>
+
+#pragma redefine_extname __atomic_is_lock_free_c __atomic_is_lock_free
+
+bool
+__atomic_is_lock_free_c(size_t size, void *ptr)
+{
+	switch (size) {
+	case 1:
+		return true;
+	case 2:
+		return (((uintptr_t)ptr & 1) == 0);
+	case 4:
+		return (((uintptr_t)ptr & 3) == 0);
+	}
+
+	return false;
+}
