Index: libcfa/src/concurrency/kernel/startup.cfa
===================================================================
--- libcfa/src/concurrency/kernel/startup.cfa	(revision 97229d6d4d0603b4f97fac22b55c583eb89341e1)
+++ libcfa/src/concurrency/kernel/startup.cfa	(revision 72a3aff1a5539f7902f2fb2ec6468b2cd5fec852)
@@ -727,4 +727,10 @@
 		}
 	#else
+		__cfaabi_dbg_debug_do(
+			// pthread has no mechanism to create the guard page in user supplied stack.
+			if ( mprotect( stack, __page_size, PROT_READ | PROT_WRITE ) == -1 ) {
+				abort( "mprotect : internal error, mprotect failure, error(%d) %s.", errno, strerror( errno ) );
+			} // if
+		);
 		free( stack );
 	#endif