Clang's unsigned integer overflow sanitizer is flagging BucketNumber as having an overflow. This seems to be intentional, and we should disable the sanitizer for this function.

PiperOrigin-RevId: 520968947

src/google/protobuf/map.h

@@ -1010,7 +1010,8 @@ class KeyMapBase : public UntypedMapBase {
   }
 
   template <typename K>
-  size_type BucketNumber(const K& k) const {
+  size_type PROTOBUF_NO_SANITIZE("unsigned-integer-overflow")
+      BucketNumber(const K& k) const {
     // We xor the hash value against the random seed so that we effectively
     // have a random hash function.
     uint64_t h = hash_function()(k) ^ seed_;

src/google/protobuf/port_def.inc

@@ -879,6 +879,12 @@ static_assert(PROTOBUF_CPLUSPLUS_MIN(201402L), "Protobuf only supports C++14 and
 #define PROTOBUF_UNUSED
 #endif
 
+#if __has_attribute(no_sanitize)
+#define PROTOBUF_NO_SANITIZE(...) __attribute__((no_sanitize(__VA_ARGS__)))
+#else
+#define PROTOBUF_NO_SANITIZE(...)
+#endif
+
 // ThreadSafeArenaz is turned off completely in opensource builds.
 
 // autoheader defines this in some circumstances