--- absl/base/config.h	2026-06-02 02:50:32.000000000 +0800
+++ absl/base/config.h	2026-06-29 16:54:43.000000000 +0800
@@ -235,7 +235,7 @@
 // compiled against libstdc++ with _GLIBCXX_HAVE_TLS defined.
 #ifdef ABSL_HAVE_TLS
 #error ABSL_HAVE_TLS cannot be directly set
-#elif (defined(__linux__)) && (defined(__clang__) || defined(_GLIBCXX_HAVE_TLS))
+#elif defined(__clang__) || defined(_GLIBCXX_HAVE_TLS)
 #define ABSL_HAVE_TLS 1
 #elif defined(__INTEL_LLVM_COMPILER)
 #define ABSL_HAVE_TLS 1
@@ -425,6 +425,7 @@
 // explicitly deprecated and will cause build failures if enabled for those
 // platforms.  We side-step the issue by not defining it here for Apple
 // platforms.
+// TODO: review correctness of the above.
 #ifdef ABSL_HAVE_SEMAPHORE_H
 #error ABSL_HAVE_SEMAPHORE_H cannot be directly set
 #elif defined(__linux__) || defined(__ros__) || defined(__VXWORKS__)
@@ -507,7 +508,8 @@
 // and
 // https://github.com/llvm/llvm-project/commit/0bc451e7e137c4ccadcd3377250874f641ca514a
 // The second has the actually correct versions, thus, is what we copy here.
-#if defined(__APPLE__) &&                                         \
+// Note, this only holds for libc++.
+#if defined(__APPLE__) && defined(_LIBCPP_VERSION) &&             \
     ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) &&   \
       __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 101300) ||  \
      (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) &&  \