--- a/include/tscore/ink_rwlock.h
+++ b/include/tscore/ink_rwlock.h
@@ -40,7 +40,7 @@
 // Instead of calling ink_rwlock_init(), an ink_rwlock instance can be initialized with one of thsee values.
 //
 ink_rwlock const INK_RWLOCK_INIT = PTHREAD_RWLOCK_INITIALIZER;
-#if defined(linux)
+#if defined(linux) && defined(__GLIBC__)
 ink_rwlock const INK_RWLOCK_INIT_NO_WRITER_STARVATION = PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP;
 #else
 // Testing indicates that for MacOS/Darwin and FreeBSD, pthread rwlocks always prevent writer starvation.
--- a/include/tscpp/util/TsSharedMutex.h
+++ b/include/tscpp/util/TsSharedMutex.h
@@ -207,7 +207,7 @@
     }
   }
 
-#if defined(linux)
+#if defined(linux) && defined(__GLIBC__)
   // Use the initializer that prevents writer starvation.
   //
   pthread_rwlock_t _lock = PTHREAD_RWLOCK_WRITER_NONRECURSIVE_INITIALIZER_NP;