diff --git a/src/gmalloc.c b/src/gmalloc.c
index 2b29f5c6c81..1faf6506167 100644
--- a/src/gmalloc.c
+++ b/src/gmalloc.c
@@ -47,11 +47,15 @@ License along with this library.  If not, see <https://www.gnu.org/licenses/>.
 #ifndef __MALLOC_HOOK_VOLATILE
 # define __MALLOC_HOOK_VOLATILE volatile
 #endif
-#ifndef HAVE_MALLOC_H
+#if !defined HAVE_MALLOC_H						\
+  || (__GLIBC__ > 2 || __GLIBC_MINOR__ >= 34)
 extern void (*__MALLOC_HOOK_VOLATILE __after_morecore_hook) (void);
-extern void (*__MALLOC_HOOK_VOLATILE __malloc_initialize_hook) (void);
 extern void *(*__morecore) (ptrdiff_t);
-#endif
+#endif /* !defined HAVE_MALLOC_H || glibc >= 2.34 */
+#if !defined HAVE_MALLOC_H						\
+  || (__GLIBC__ > 2 || __GLIBC_MINOR__ >= 24)
+extern void (*__MALLOC_HOOK_VOLATILE __malloc_initialize_hook) (void);
+#endif /* !defined HAVE_MALLOC_H || glibc >= 2.24 */
 
 /* If HYBRID_MALLOC is defined, then temacs will use malloc,
    realloc... as defined in this file (and renamed gmalloc,