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Co-authored-by: Ralf Jung <[email protected]>

Author: tiif

tests/pass-dep/libc/libc-mem.rs

@@ -190,7 +190,8 @@ fn test_memalign() {
         let align = 64;
         let size = 0;
         assert_eq!(libc::posix_memalign(&mut ptr, align, size), 0);
-        // Non-null pointer is returned if size == 0
+        // Non-null pointer is returned if size == 0.
+        // (This is not a guarantee, it just reflects our current behavior.)
         assert!(!ptr.is_null());
         assert!(ptr.is_aligned_to(align));
         libc::free(ptr);