Merge from gnulib.

This incorporates:
2013-09-24 manywarnings: enable nicer gcc warning messages
2013-09-23 warnings: port --enable-gcc-warnings to Solaris Studio 12.3
2013-09-21 timespec: use the new TIMESPEC_RESOLUTION elsewhere
* configure.ac (WERROR_CFLAGS): Omit -fdiagnostics-show-option
and -funit-at-a-time, since manywarnings does that for us now.

6 files changed, 21 insertions, 13 deletions

diff --git a/ChangeLog b/ChangeLog
index d2a27b7b6ee..f8a219d6a15 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2013-09-25  Paul Eggert  <eggert@cs.ucla.edu>
+
+	Merge from gnulib, incorporating:
+	2013-09-24 manywarnings: enable nicer gcc warning messages
+	2013-09-23 warnings: port --enable-gcc-warnings to Solaris Studio 12.3
+	2013-09-21 timespec: use the new TIMESPEC_RESOLUTION elsewhere
+	* configure.ac (WERROR_CFLAGS): Omit -fdiagnostics-show-option
+	and -funit-at-a-time, since manywarnings does that for us now.
+
 2013-09-23  Jan Djärv  <jan.h.d@swipnet.se>
 
 	* configure.ac: With clang, check for and use -Wno-switch,
diff --git a/configure.ac b/configure.ac
index 16259f01ed2..53426b67e45 100644
--- a/configure.ac
+++ b/configure.ac
@@ -886,9 +886,6 @@ else
     gl_WARN_ADD([-Wno-unused-value])
   fi
 
-  gl_WARN_ADD([-fdiagnostics-show-option])
-  gl_WARN_ADD([-funit-at-a-time])
-
   AC_DEFINE([lint], [1], [Define to 1 if the compiler is checking for lint.])
   AH_VERBATIM([FORTIFY_SOURCE],
   [/* Enable compile-time and run-time bounds-checking, and some warnings,
diff --git a/lib/timespec-add.c b/lib/timespec-add.c
index 51323a63207..d628237fe56 100644
--- a/lib/timespec-add.c
+++ b/lib/timespec-add.c
@@ -18,7 +18,7 @@
 /* Written by Paul Eggert.  */
 
 /* Return the sum of two timespec values A and B.  On overflow, return
-   an extremal value.  This assumes 0 <= tv_nsec <= 999999999.  */
+   an extremal value.  This assumes 0 <= tv_nsec < TIMESPEC_RESOLUTION.  */
 
 #include <config.h>
 #include "timespec.h"
@@ -58,7 +58,7 @@ timespec_add (struct timespec a, struct timespec b)
         {
         high_overflow:
           rs = TYPE_MAXIMUM (time_t);
-          rns = 999999999;
+          rns = TIMESPEC_RESOLUTION - 1;
         }
     }
   else
diff --git a/lib/timespec-sub.c b/lib/timespec-sub.c
index b164a8380d0..3f3adea28d6 100644
--- a/lib/timespec-sub.c
+++ b/lib/timespec-sub.c
@@ -18,8 +18,8 @@
 /* Written by Paul Eggert.  */
 
 /* Return the difference between two timespec values A and B.  On
-   overflow, return an extremal value.  This assumes 0 <= tv_nsec <=
-   999999999.  */
+   overflow, return an extremal value.  This assumes 0 <= tv_nsec <
+   TIMESPEC_RESOLUTION.  */
 
 #include <config.h>
 #include "timespec.h"
@@ -58,7 +58,7 @@ timespec_sub (struct timespec a, struct timespec b)
       else
         {
           rs = TYPE_MAXIMUM (time_t);
-          rns = 999999999;
+          rns = TIMESPEC_RESOLUTION - 1;
         }
     }
   else
diff --git a/m4/manywarnings.m4 b/m4/manywarnings.m4
index be6d4c91c50..80b2476d250 100644
--- a/m4/manywarnings.m4
+++ b/m4/manywarnings.m4
@@ -1,4 +1,4 @@
-# manywarnings.m4 serial 5
+# manywarnings.m4 serial 6
 dnl Copyright (C) 2008-2013 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -204,6 +204,8 @@ AC_DEFUN([gl_MANYWARN_ALL_GCC],
     -Wvla \
     -Wvolatile-register-var \
     -Wwrite-strings \
+    -fdiagnostics-show-option \
+    -funit-at-a-time \
     \
     ; do
     gl_manywarn_set="$gl_manywarn_set $gl_manywarn_item"
diff --git a/m4/warnings.m4 b/m4/warnings.m4
index 5f5da51606b..e3d239b64ff 100644
--- a/m4/warnings.m4
+++ b/m4/warnings.m4
@@ -1,4 +1,4 @@
-# warnings.m4 serial 10
+# warnings.m4 serial 11
 dnl Copyright (C) 2008-2013 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -36,9 +36,9 @@ AC_CACHE_CHECK([whether _AC_LANG compiler handles $1], m4_defn([gl_Warn]), [
   gl_save_compiler_FLAGS="$gl_Flags"
   gl_AS_VAR_APPEND(m4_defn([gl_Flags]),
     [" $gl_unknown_warnings_are_errors ]m4_defn([gl_Positive])["])
-  AC_COMPILE_IFELSE([m4_default([$4], [AC_LANG_PROGRAM([])])],
-                    [AS_VAR_SET(gl_Warn, [yes])],
-                    [AS_VAR_SET(gl_Warn, [no])])
+  AC_LINK_IFELSE([m4_default([$4], [AC_LANG_PROGRAM([])])],
+                 [AS_VAR_SET(gl_Warn, [yes])],
+                 [AS_VAR_SET(gl_Warn, [no])])
   gl_Flags="$gl_save_compiler_FLAGS"
 ])
 AS_VAR_IF(gl_Warn, [yes], [$2], [$3])