diff --git a/libc/include/pthread.h b/libc/include/pthread.h
index ae4fdce..c34d1a3 100644
--- a/libc/include/pthread.h
+++ b/libc/include/pthread.h
@@ -207,7 +207,7 @@
 pthread_t pthread_self(void) __attribute_const__;
 
 #if defined(__USE_GNU)
-int pthread_getname_np(pthread_t, char* _Nonnull, size_t) __INTRODUCED_IN_FUTURE;
+int pthread_getname_np(pthread_t, char* _Nonnull, size_t) __INTRODUCED_IN(26);
 #endif
 /* TODO: this should be __USE_GNU too. */
 int pthread_setname_np(pthread_t, const char* _Nonnull);