--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2009-08-10  Bruno Haible  <bruno@clisp.org>
+
+	Don't optimize AC_LIBOBJs, as they may appear in different contexts.
+	* m4/close.m4 (gl_REPLACE_CLOSE): Execute AC_LIBOBJ unconditionally,
+	not only the first time.
+	* m4/fclose.m4 (gl_REPLACE_FCLOSE): Likewise.
+	* m4/open.m4 (gl_REPLACE_OPEN): Likewise.
+	* m4/strstr.m4 (gl_FUNC_STRSTR): Execute AC_LIBOBJ when REPLACE_STRSTR
+	is 1, not only the the first time.
+
 2009-08-10  Bruno Haible  <bruno@clisp.org>
 
 	Make it possible to use module 'gethostname' without module 'close'.

--- a/m4/close.m4
+++ b/m4/close.m4
@@ -1,4 +1,4 @@
-# close.m4 serial 4
+# close.m4 serial 5
 dnl Copyright (C) 2008-2009 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -20,9 +20,7 @@
 AC_DEFUN([gl_REPLACE_CLOSE],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
-  if test $REPLACE_CLOSE != 1; then
-    AC_LIBOBJ([close])
-  fi
   REPLACE_CLOSE=1
+  AC_LIBOBJ([close])
   gl_REPLACE_FCLOSE
 ])

--- a/m4/fclose.m4
+++ b/m4/fclose.m4
@@ -1,5 +1,5 @@
-# fclose.m4 serial 1
-dnl Copyright (C) 2008 Free Software Foundation, Inc.
+# fclose.m4 serial 2
+dnl Copyright (C) 2008-2009 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.
@@ -11,8 +11,6 @@
 AC_DEFUN([gl_REPLACE_FCLOSE],
 [
   AC_REQUIRE([gl_STDIO_H_DEFAULTS])
-  if test $REPLACE_FCLOSE != 1; then
-    AC_LIBOBJ([fclose])
-  fi
   REPLACE_FCLOSE=1
+  AC_LIBOBJ([fclose])
 ])

--- a/m4/open.m4
+++ b/m4/open.m4
@@ -1,4 +1,4 @@
-# open.m4 serial 6
+# open.m4 serial 7
 dnl Copyright (C) 2007-2009 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -51,11 +51,9 @@
 AC_DEFUN([gl_REPLACE_OPEN],
 [
   AC_REQUIRE([gl_FCNTL_H_DEFAULTS])
-  if test $REPLACE_OPEN != 1; then
-    AC_LIBOBJ([open])
-    gl_PREREQ_OPEN
-  fi
   REPLACE_OPEN=1
+  AC_LIBOBJ([open])
+  gl_PREREQ_OPEN
 ])
 
 # Prerequisites of lib/open.c.

--- a/m4/strstr.m4
+++ b/m4/strstr.m4
@@ -1,4 +1,4 @@
-# strstr.m4 serial 6
+# strstr.m4 serial 7
 dnl Copyright (C) 2008, 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,
@@ -71,7 +71,9 @@
       ])
     if test "$gl_cv_func_strstr_linear" != yes; then
       REPLACE_STRSTR=1
-      AC_LIBOBJ([strstr])
     fi
   fi
+  if test $REPLACE_STRSTR = 1; then
+    AC_LIBOBJ([strstr])
+  fi
 ]) # gl_FUNC_STRSTR