Since M_CHECK_ACTION is only defined in <malloc.h>, it is confusing that the
test program tests it _before_ having included <malloc.h>. (Fortunately this
does not produce a bug, since HAVE_DECL_ALARM is 1 on glibc.) But anyway,
it's better written like this:
2024-10-26 Bruno Haible <br...@clisp.org>
regex: Make configure test more maintainable.
* m4/regex.m4 (gl_REGEX): Include <malloc.h> before testing for
M_CHECK_ACTION.
diff --git a/m4/regex.m4 b/m4/regex.m4
index 64fa7e9146..18f36804c4 100644
--- a/m4/regex.m4
+++ b/m4/regex.m4
@@ -1,5 +1,5 @@
# regex.m4
-# serial 75
+# serial 76
dnl Copyright (C) 1996-2001, 2003-2024 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -40,15 +40,15 @@ AC_DEFUN([gl_REGEX]
#include <limits.h>
#include <string.h>
+ #if HAVE_MALLOC_H
+ # include <malloc.h> /* defines M_CHECK_ACTION on glibc */
+ #endif
+
#if defined M_CHECK_ACTION || HAVE_DECL_ALARM
# include <signal.h>
# include <unistd.h>
#endif
- #if HAVE_MALLOC_H
- # include <malloc.h>
- #endif
-
#ifdef M_CHECK_ACTION
/* Exit with distinguishable exit code. */
static void sigabrt_no_core (int sig) { raise (SIGTERM); }
