Re: link-warning usage improvements

[Bruno Haible]

Eric Blake wrote:
> +       * m4/arpa_inet_h.m4 (gl_HEADER_ARPA_INET)
> +       (gl_ARPA_INET_H_DEFAULTS): Drop unneeded variable.
> +       * m4/ctype.m4 (gl_CTYPE_H_DEFAULTS): Likewise.
> +       * m4/isblank.m4 (gl_FUNC_ISBLANK): Likewise.
> +       * m4/dirent_h.m4 (gl_REPLACE_DIRENT_H, gl_DIRENT_H_DEFAULTS):
> +       Likewise.
> +       * m4/inttypes.m4 (gl_INTTYPES_H): Likewise.
> +       * m4/langinfo_h.m4 (gl_LANGINFO_H): Likewise.
> +       * m4/locale_h.m4 (gl_REPLACE_LOCALE_H, gl_LOCALE_H_DEFAULTS):
> +       Likewise.
> +       * m4/spawn_h.m4 (gl_REPLACE_SPAWN_H, gl_SPAWN_H_DEFAULTS):
> +       Likewise.
> +       * m4/sys_file_h.m4 (gl_HEADER_SYS_FILE_H): Likewise.
> +       * m4/sys_ioctl_h.m4 (gl_SYS_IOCTL_H, gl_REPLACE_SYS_IOCTL_H)
> +       (gl_SYS_IOCTL_H_DEFAULTS): Likewise.
> +       * m4/sys_select_h.m4 (gl_HEADER_SYS_SELECT): Likewise.
> +       * m4/sys_times_h.m4 (gl_SYS_TIMES_H): Likewise.
> +       * m4/sys_utsname_h.m4 (gl_SYS_UTSNAME_H)
> +       (gl_SYS_UTSNAME_H_DEFAULTS): Likewise.
> +       * m4/wchar.m4 (gl_WCHAR_H, gl_REPLACE_WCHAR_H)
> +       (gl_WCHAR_H_DEFAULTS): Likewise.

Some further updates of the gl_REPLACE_*_H macros and comments. I think
these gl_REPLACE_*_H macros should be kept; we don't know how the idioms
will evolve in the future.


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

        * m4/wchar.m4 (gl_WCHAR_H): Remove gl_STDDEF_H invocation.
        (gl_REPLACE_WCHAR_H): Turn into a no-op.
        * m4/arpa_inet_h.m4 (gl_REPLACE_ARPA_INET_H): Likewise.
        * m4/dirent_h.m4 (gl_REPLACE_DIRENT_H): Likewise.
        * m4/locale_h.m4 (gl_REPLACE_LOCALE_H): Likewise.
        * m4/spawn_h.m4 (gl_REPLACE_SPAWN_H): Likewise.
        * m4/sys_ioctl_h.m4 (gl_REPLACE_SYS_IOCTL_H): Likewise.

--- m4/wchar.m4.orig    Thu Dec 31 22:35:47 2009
+++ m4/wchar.m4 Thu Dec 31 22:35:01 2009
@@ -28,9 +28,6 @@
   fi
   AC_SUBST([HAVE_WINT_T])
 
-  dnl If <stddef.h> is replaced, then <wchar.h> must also be replaced.
-  AC_REQUIRE([gl_STDDEF_H])
-
   dnl Prepare for creating substitute <wchar.h>.
   dnl Do it always: WCHAR_H may be empty here but can be set later.
   dnl Check for <wchar.h> (missing in Linux uClibc when built without wide
@@ -42,8 +39,7 @@
     HAVE_WCHAR_H=0
   fi
   AC_SUBST([HAVE_WCHAR_H])
-  dnl Execute this unconditionally, because WCHAR_H may be set by other
-  dnl modules, after this code is executed.
+  dnl <wchar.h> is always overridden, because of GNULIB_POSIXCHECK.
   gl_CHECK_NEXT_HEADERS([wchar.h])
 ])
 
@@ -98,7 +94,7 @@
 dnl Unconditionally enables the replacement of <wchar.h>.
 AC_DEFUN([gl_REPLACE_WCHAR_H],
 [
-  AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
+  dnl This is a no-op, because <wchar.h> is always overridden.
   :
 ])
 
--- m4/arpa_inet_h.m4.orig      Thu Dec 31 22:35:47 2009
+++ m4/arpa_inet_h.m4   Thu Dec 31 22:31:01 2009
@@ -19,15 +19,14 @@
     HAVE_ARPA_INET_H=0
   fi
   AC_SUBST([HAVE_ARPA_INET_H])
-  dnl Execute this unconditionally, because ARPA_INET_H may be set by other
-  dnl modules, after this code is executed.
+  dnl <arpa/inet.h> is always overridden, because of GNULIB_POSIXCHECK.
   gl_CHECK_NEXT_HEADERS([arpa/inet.h])
 ])
 
 dnl Unconditionally enables the replacement of <arpa/inet.h>.
 AC_DEFUN([gl_REPLACE_ARPA_INET_H],
 [
-  AC_REQUIRE([gl_ARPA_INET_H_DEFAULTS])
+  dnl This is a no-op, because <arpa/inet.h> is always overridden.
   :
 ])
 
--- m4/dirent_h.m4.orig Thu Dec 31 22:35:47 2009
+++ m4/dirent_h.m4      Thu Dec 31 22:35:01 2009
@@ -12,15 +12,14 @@
   dnl once only, before all statements that occur in other macros.
   AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
 
-  dnl Execute this unconditionally, because DIRENT_H may be set by other
-  dnl modules, after this code is executed.
+  dnl <dirent.h> is always overridden, because of GNULIB_POSIXCHECK.
   gl_CHECK_NEXT_HEADERS([dirent.h])
 ])
 
 dnl Unconditionally enables the replacement of <dirent.h>.
 AC_DEFUN([gl_REPLACE_DIRENT_H],
 [
-  AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
+  dnl This is a no-op, because <dirent.h> is always overridden.
   :
 ])
 
--- m4/locale_h.m4.orig Thu Dec 31 22:35:47 2009
+++ m4/locale_h.m4      Thu Dec 31 22:35:01 2009
@@ -48,8 +48,7 @@
   fi
   AC_SUBST([HAVE_XLOCALE_H])
 
-  dnl Execute this unconditionally, because LOCALE_H may be set by other
-  dnl modules, after this code is executed.
+  dnl <locale.h> is always overridden, because of GNULIB_POSIXCHECK.
   gl_CHECK_NEXT_HEADERS([locale.h])
 
   if test -n "$STDDEF_H" \
@@ -62,7 +61,7 @@
 dnl Unconditionally enables the replacement of <locale.h>.
 AC_DEFUN([gl_REPLACE_LOCALE_H],
 [
-  AC_REQUIRE([gl_LOCALE_H_DEFAULTS])
+  dnl This is a no-op, because <locale.h> is always overridden.
   :
 ])
 
--- m4/spawn_h.m4.orig  Thu Dec 31 22:35:47 2009
+++ m4/spawn_h.m4       Thu Dec 31 22:35:01 2009
@@ -12,8 +12,7 @@
   dnl once only, before all statements that occur in other macros.
   AC_REQUIRE([gl_SPAWN_H_DEFAULTS])
 
-  dnl Execute this unconditionally, because SPAWN_H may be set by other
-  dnl modules, after this code is executed.
+  dnl <spawn.h> is always overridden, because of GNULIB_POSIXCHECK.
   gl_CHECK_NEXT_HEADERS([spawn.h])
 
   AC_CHECK_HEADERS_ONCE([spawn.h])
@@ -40,7 +39,7 @@
 dnl Unconditionally enables the replacement of <spawn.h>.
 AC_DEFUN([gl_REPLACE_SPAWN_H],
 [
-  AC_REQUIRE([gl_SPAWN_H_DEFAULTS])
+  dnl This is a no-op, because <spawn.h> is always overridden.
   :
 ])
 
--- m4/sys_ioctl_h.m4.orig      Thu Dec 31 22:35:47 2009
+++ m4/sys_ioctl_h.m4   Thu Dec 31 22:35:01 2009
@@ -31,15 +31,14 @@
     HAVE_SYS_IOCTL_H=0
   fi
   AC_SUBST([HAVE_SYS_IOCTL_H])
-  dnl Execute this unconditionally, because SYS_IOCTL_H may be set by other
-  dnl modules, after this code is executed.
+  dnl <sys/ioctl.h> is always overridden, because of GNULIB_POSIXCHECK.
   gl_CHECK_NEXT_HEADERS([sys/ioctl.h])
 ])
 
 dnl Unconditionally enables the replacement of <sys/ioctl.h>.
 AC_DEFUN([gl_REPLACE_SYS_IOCTL_H],
 [
-  AC_REQUIRE([gl_SYS_IOCTL_H_DEFAULTS])
+  dnl This is a no-op, because <sys/ioctl.h> is always overridden.
   :
 ])