maint.mk: import changes to syntax-check macros from coreutils

[gnulib.git] / m4 / strerror.m4

diff --git a/m4/strerror.m4 b/m4/strerror.m4
index 52f3e3f..8c16ca9 100644 (file)
--- a/m4/strerror.m4
+++ b/m4/strerror.m4
@@ -1,5 +1,5 @@
-# strerror.m4 serial 4
-dnl Copyright (C) 2002, 2007 Free Software Foundation, Inc.
+# strerror.m4 serial 9
+dnl Copyright (C) 2002, 2007-2008 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.
@@ -7,7 +7,7 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_STRERROR],
 [
   AC_REQUIRE([gl_FUNC_STRERROR_SEPARATE])
-  if test $gl_cv_func_working_strerror = no; then
+  if test $REPLACE_STRERROR = 1; then
     AC_LIBOBJ([strerror])
     AC_DEFINE_UNQUOTED([REPLACE_STRERROR], [$REPLACE_STRERROR],
       [Define this to 1 if strerror is broken.])
@@ -17,33 +17,52 @@ AC_DEFUN([gl_FUNC_STRERROR],
 # Like gl_FUNC_STRERROR, except prepare for separate compilation (no AC_LIBOBJ).
 AC_DEFUN([gl_FUNC_STRERROR_SEPARATE],
 [
-  AC_CHECK_FUNCS_ONCE([strerror])
-  gl_PREREQ_STRERROR
-  if test $ac_cv_func_strerror = no; then
-    HAVE_DECL_STRERROR=0
-    gl_cv_func_working_strerror=no
-  else
+  AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
+  AC_REQUIRE([gl_HEADER_ERRNO_H])
+  if test -z "$ERRNO_H"; then
     AC_CACHE_CHECK([for working strerror function],
      [gl_cv_func_working_strerror],
      [AC_RUN_IFELSE(
-       [AC_LANG_PROGRAM([
-#include <string.h>
-        ], [return !*strerror (-2);])],
-       [gl_cv_func_working_strerror=yes], [gl_cv_func_working_strerror=no],
-       [dnl assume success except on Interix
-       AC_EGREP_CPP([assuming success], [
-#ifndef __INTERIX
-  assuming success
-#endif
-       ], [gl_cv_func_working_strerror=yes],
-       [gl_cv_func_working_strerror=no])])])
-    if test $gl_cv_func_working_strerror = no ; then
+        [AC_LANG_PROGRAM(
+           [[#include <string.h>
+           ]],
+           [[return !*strerror (-2);]])],
+        [gl_cv_func_working_strerror=yes],
+        [gl_cv_func_working_strerror=no],
+        [dnl Assume crossbuild works if it compiles.
+         AC_COMPILE_IFELSE(
+           [AC_LANG_PROGRAM(
+              [[#include <string.h>
+              ]],
+              [[return !*strerror (-2);]])],
+           [gl_cv_func_working_strerror=yes],
+           [gl_cv_func_working_strerror=no])
+      ])
+    ])
+    if test $gl_cv_func_working_strerror = no; then
+      dnl The system's strerror() fails to return a string for out-of-range
+      dnl integers. Replace it.
       REPLACE_STRERROR=1
     fi
+  else
+    dnl The system's strerror() cannot know about the new errno values we add
+    dnl to <errno.h>. Replace it.
+    REPLACE_STRERROR=1
+  fi
+  if test $REPLACE_STRERROR = 1; then
+    gl_PREREQ_STRERROR
   fi
 ])
 
 # Prerequisites of lib/strerror.c.
 AC_DEFUN([gl_PREREQ_STRERROR], [
-  :
+  AC_CHECK_DECLS([strerror])
+  AC_CHECK_HEADERS_ONCE([sys/socket.h])
+  if test $ac_cv_header_sys_socket_h != yes; then
+    dnl We cannot use AC_CHECK_HEADERS_ONCE here, because that would make
+    dnl the check for those headers unconditional; yet cygwin reports
+    dnl that the headers are present but cannot be compiled (since on
+    dnl cygwin, all socket information should come from sys/socket.h).
+    AC_CHECK_HEADERS([winsock2.h])
+  fi
 ])