Re: link-warning usage improvements

[Bruno Haible]

Eric Blake wrote:
>  2009-12-31  Eric Blake  <address@hidden>
> 
> +       sys_times, sys_utsname: use include_next
> +       * m4/sys_times_h.m4 (gl_SYS_TIMES_H): Support wrapping an existing
> +       header.
> +       (gl_SYS_TIMES_H_DEFAULTS): Add another variable.
> +       * m4/sys_utsname_h.m4 (gl_SYS_UTSNAME_H)
> +       (gl_SYS_UTSNAME_H_DEFAULTS): Likewise.
> +       * modules/sys_times (Depends-on): Add include_next.
> +       (Makefile.am): Substitute additional values.
> +       * modules/sys_utsname (Depends-on, Makefile.am): Likewise.
> +       * lib/sys_times.in.h (includes): Include native header, if
> +       available.
> +       * lib/sys_utsname.in.h (includes): Likewise.
> +       * tests/test-sys_times.c (main): Enhance test.

The sys_utsname part looks correct.

The sys_times part (btw, it would be easier to read if it were two separate
commits) introduces a regression: a compilation failure on mingw:

  $ ./gnulib-tool --create-testdir --dir=... --with-tests times
then on mingw:
  $ make
  ...
  test-times.c:24: error: `times' undeclared here (not in a function)
  test-times.c: In function `main':
  test-times.c:52: warning: implicit declaration of function `times'
  make[4]: *** [test-times.o] Error 1

The reason is that HAVE_TIMES is set to 1 on all platforms, even mingw.
This fixes it:


2009-12-31  Bruno Haible  <address@hidden>

        times: Update after sys_times changed.
        * m4/times.m4: New file, extracted from modules/times. Set HAVE_TIMES.
        * modules/times (Files): Add it.
        (configure.ac): Invoke gl_FUNC_TIMES.

Changing permissions from . to 100644
--- m4/times.m4.orig    Tue Apr 14 12:31:40 2009
+++ m4/times.m4 Thu Dec 31 21:25:43 2009
@@ -0,0 +1,15 @@
+# times.m4 serial 1
+dnl Copyright (C) 2009 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_FUNC_TIMES],
+[
+  AC_REQUIRE([gl_SYS_TIMES_H_DEFAULTS])
+  AC_CHECK_FUNCS_ONCE([times])
+  if test $ac_cv_func_times = no; then
+    HAVE_TIMES=0
+    AC_LIBOBJ([times])
+  fi
+])
--- modules/times.orig  Thu Dec 31 21:30:09 2009
+++ modules/times       Thu Dec 31 21:25:29 2009
@@ -3,15 +3,13 @@
 
 Files:
 lib/times.c
+m4/times.m4
 
 Depends-on:
 sys_times
 
 configure.ac:
-AC_CHECK_FUNCS_ONCE([times])
-if test $ac_cv_func_times = no; then
-  AC_LIBOBJ([times])
-fi
+gl_FUNC_TIMES
 gl_SYS_TIMES_MODULE_INDICATOR([times])
 
 Makefile.am: