Merge pull request #1401 from AtariDreams:apple

PiperOrigin-RevId: 511270860
Change-Id: Ib7de8c72505bf141d450f950074a27f9f4f1613c

Author: copybara-github

absl/hash/internal/hash.h

@@ -1136,7 +1136,8 @@ class ABSL_DLL MixingHashState : public HashStateBase<MixingHashState> {
   // probably per-build and not per-process.
   ABSL_ATTRIBUTE_ALWAYS_INLINE static uint64_t Seed() {
 #if (!defined(__clang__) || __clang_major__ > 11) && \
-    !defined(__apple_build_version__)
+    (!defined(__apple_build_version__) ||            \
+     __apple_build_version__ >= 19558921)  // Xcode 12
     return static_cast<uint64_t>(reinterpret_cast<uintptr_t>(&kSeed));
 #else
     // Workaround the absence of