From: Eric Blake <eblake@redhat.com>
Date: Mon, 30 Aug 2010 15:51:11 +0000 (-0600)
Subject: fortran: always avoid AC_LANG_CONFTEST warning
X-Git-Tag: v2.68~36
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=30378453ea71e8a53c3dcc401ffa64b43353a64b;p=thirdparty%2Fautoconf.git

fortran: always avoid AC_LANG_CONFTEST warning

* lib/autoconf/lang.m4 (AC_LANG_CONFTEST()): Make the default
match the fact that the default AC_LANG_SOURCE does not inline
confdefs.h in the first place.
* lib/autoconf/fortran.m4 (AC_FC_FREEFORM, AC_FC_FIXEDFORM)
(AC_FC_LINE_LENGTH, __AC_FC_NAME_MANGLING): Revert previous use of
AC_LANG_DEFINES_PROVIDED.
Suggested by Ralf Wildenhues.

Signed-off-by: Eric Blake <eblake@redhat.com>
---

diff --git a/ChangeLog b/ChangeLog
index c3cec30e9..5d3ac87c5 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,14 @@
 2010-08-30  Eric Blake  <eblake@redhat.com>
 
+	fortran: always avoid AC_LANG_CONFTEST warning
+	* lib/autoconf/lang.m4 (AC_LANG_CONFTEST()): Make the default
+	match the fact that the default AC_LANG_SOURCE does not inline
+	confdefs.h in the first place.
+	* lib/autoconf/fortran.m4 (AC_FC_FREEFORM, AC_FC_FIXEDFORM)
+	(AC_FC_LINE_LENGTH, __AC_FC_NAME_MANGLING): Revert previous use of
+	AC_LANG_DEFINES_PROVIDED.
+	Suggested by Ralf Wildenhues.
+
 	config.status: minimize use of $tmp
 	* lib/autoconf/status.m4 (_AC_OUTPUT_MAIN_LOOP)
 	(_AC_OUTPUT_FILES_PREPARE, _AC_OUTPUT_FILE)
diff --git a/lib/autoconf/fortran.m4 b/lib/autoconf/fortran.m4
index 5e48468db..e8f7bbcd9 100644
--- a/lib/autoconf/fortran.m4
+++ b/lib/autoconf/fortran.m4
@@ -897,8 +897,8 @@ AC_DEFUN([__AC_FC_NAME_MANGLING],
 [_AC_FORTRAN_ASSERT()dnl
 AC_CACHE_CHECK([for _AC_LANG name-mangling scheme],
 	       ac_cv_[]_AC_LANG_ABBREV[]_mangling,
-[AC_COMPILE_IFELSE([AC_LANG_DEFINES_PROVIDED
-[      subroutine foobar()
+[AC_COMPILE_IFELSE(
+[[      subroutine foobar()
       return
       end
       subroutine foo_bar()
@@ -1186,7 +1186,7 @@ for ac_flag in none -ffree-form -FR -free -qfree -Mfree -Mfreeform \
 do
   test "x$ac_flag" != xnone && FCFLAGS="$ac_fc_freeform_FCFLAGS_save $ac_flag"
 dnl Use @&t@ below to ensure that editors don't turn 8+ spaces into tab.
-  AC_COMPILE_IFELSE([AC_LANG_DEFINES_PROVIDED[
+  AC_COMPILE_IFELSE([[
   program freeform
        ! FIXME: how to best confuse non-freeform compilers?
        print *, 'Hello ', &
@@ -1241,7 +1241,7 @@ for ac_flag in none -ffixed-form -fixed -qfixed -Mfixed -fixedform "-f fixed" \
 	       +source=fixed -fix
 do
   test "x$ac_flag" != xnone && FCFLAGS="$ac_fc_fixedform_FCFLAGS_save $ac_flag"
-  AC_COMPILE_IFELSE([AC_LANG_DEFINES_PROVIDED[
+  AC_COMPILE_IFELSE([[
 C     This comment should confuse free-form compilers.
       program main
       end]],
@@ -1324,7 +1324,7 @@ for ac_flag in none \
 	       "-W $ac_fc_line_len" +extend_source -wide -e
 do
   test "x$ac_flag" != xnone && FCFLAGS="$ac_fc_line_length_FCFLAGS_save $ac_flag"
-  AC_COMPILE_IFELSE([AC_LANG_DEFINES_PROVIDED[$ac_fc_line_length_test
+  AC_COMPILE_IFELSE([[$ac_fc_line_length_test
       end subroutine]],
 		    [ac_cv_fc_line_length=$ac_flag; break])
 done
diff --git a/lib/autoconf/lang.m4 b/lib/autoconf/lang.m4
index bd4b68b70..d2e98f9ed 100644
--- a/lib/autoconf/lang.m4
+++ b/lib/autoconf/lang.m4
@@ -201,9 +201,13 @@ AC_DEFUN([AC_LANG_CONFTEST],
 # AC_LANG_CONFTEST()(BODY)
 # ------------------------
 # Default implementation of AC_LANG_CONFTEST.
+# This version assumes that you can't inline confdefs.h into your
+# language, and as such, it is safe to blindly call
+# AC_LANG_DEFINES_PROVIDED.  Language-specific overrides should
+# remove this call if AC_LANG_SOURCE does inline confdefs.h.
 m4_define([AC_LANG_CONFTEST()],
 [cat > conftest.$ac_ext <<_ACEOF
-$1
+AC_LANG_DEFINES_PROVIDED[]$1
 _ACEOF])
 
 # AC_LANG_DEFINES_PROVIDED