gettimeofday: Avoid bad guess when cross-compiling to glibc systems.

* m4/gettimeofday.m4 (gl_FUNC_GETTIMEOFDAY_CLOBBER): Require
AC_CANONICAL_HOST. When cross-compiling, guess no on glibc platforms.

diff --git a/ChangeLog b/ChangeLog
index 9d98f80..4d14dae 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2012-05-05  Bruno Haible  <bruno@clisp.org>
+
+       gettimeofday: Avoid bad guess when cross-compiling to glibc systems.
+       * m4/gettimeofday.m4 (gl_FUNC_GETTIMEOFDAY_CLOBBER): Require
+       AC_CANONICAL_HOST. When cross-compiling, guess no on glibc platforms.
+
 2012-05-04  Bruno Haible  <bruno@clisp.org>
 
        Tweak last commit.

diff --git a/m4/gettimeofday.m4 b/m4/gettimeofday.m4
index dc68c43..2e65eb5 100644 (file)
--- a/m4/gettimeofday.m4
+++ b/m4/gettimeofday.m4
@@ -1,4 +1,4 @@
-# serial 18
+# serial 19
 
 # Copyright (C) 2001-2003, 2005, 2007, 2009-2012 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -82,6 +82,7 @@ dnl the wrapper functions that work around the problem.
 AC_DEFUN([gl_FUNC_GETTIMEOFDAY_CLOBBER],
 [
  AC_REQUIRE([gl_HEADER_SYS_TIME_H])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
 
  AC_CACHE_CHECK([whether gettimeofday clobbers localtime buffer],
   [gl_cv_func_gettimeofday_clobber],
@@ -104,15 +105,23 @@ AC_DEFUN([gl_FUNC_GETTIMEOFDAY_CLOBBER],
         ]])],
      [gl_cv_func_gettimeofday_clobber=no],
      [gl_cv_func_gettimeofday_clobber=yes],
-     dnl When crosscompiling, assume it is broken.
-     [gl_cv_func_gettimeofday_clobber=yes])])
+     [# When cross-compiling:
+      case "$host_os" in
+                # Guess all is fine on glibc systems.
+        *-gnu*) gl_cv_func_gettimeofday_clobber="guessing no" ;;
+                # If we don't know, assume the worst.
+        *)      gl_cv_func_gettimeofday_clobber="guessing yes" ;;
+      esac
+     ])])
 
- if test $gl_cv_func_gettimeofday_clobber = yes; then
-   REPLACE_GETTIMEOFDAY=1
-   gl_GETTIMEOFDAY_REPLACE_LOCALTIME
-   AC_DEFINE([GETTIMEOFDAY_CLOBBERS_LOCALTIME], [1],
-     [Define if gettimeofday clobbers the localtime buffer.])
- fi
+ case "$gl_cv_func_gettimeofday_clobber" in
+   *yes)
+     REPLACE_GETTIMEOFDAY=1
+     gl_GETTIMEOFDAY_REPLACE_LOCALTIME
+     AC_DEFINE([GETTIMEOFDAY_CLOBBERS_LOCALTIME], [1],
+       [Define if gettimeofday clobbers the localtime buffer.])
+     ;;
+ esac
 ])
 
 AC_DEFUN([gl_GETTIMEOFDAY_REPLACE_LOCALTIME], [