added checks for existence of warning flags

git-svn-id: svn://scm.gforge.inria.fr/svn/mpc/trunk@106 211d60ee-9f03-0410-a15a-8952a2c7a4e4

2 files changed, 106 insertions, 3 deletions

diff --git a/configure.ac b/configure.ac
index 8a21214..4ad311e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,3 +1,101 @@
+##### http://autoconf-archive.cryp.to/ax_c_check_flag.html
+#
+# SYNOPSIS
+#
+#
+AX_C_CHECK_FLAG(FLAG-TO-CHECK,[PROLOGUE],[BODY],[ACTION-IF-SUCCESS],[ACTION-IF-FAILURE])
+#
+# DESCRIPTION
+#
+#   This macro tests if the C compiler supports the flag FLAG-TO-CHECK.
+#   If successfull execute ACTION-IF-SUCCESS otherwise
+#   ACTION-IF-FAILURE. PROLOGUE and BODY are optional and should be
+#   used as in AC_LANG_PROGRAM macro.
+#
+#   This code is inspired from KDE_CHECK_COMPILER_FLAG macro. Thanks to
+#   Bogdan Drozdowski <bogdandr@op.pl> for testing and bug fixes.
+#
+# LAST MODIFICATION
+#
+#   2007-11-26
+#
+# COPYLEFT
+#
+#   Copyright (c) 2007 Francesco Salvestrini <salvestrini@users.sourceforge.net>
+#
+#   This program is free software; you can redistribute it and/or
+#   modify it under the terms of the GNU General Public License as
+#   published by the Free Software Foundation; either version 2 of the
+#   License, or (at your option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+#   General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with this program; if not, write to the Free Software
+#   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+#   02111-1307, USA.
+#
+#   As a special exception, the respective Autoconf Macro's copyright
+#   owner gives unlimited permission to copy, distribute and modify the
+#   configure scripts that are the output of Autoconf when processing
+#   the Macro. You need not follow the terms of the GNU General Public
+#   License when using or distributing such scripts, even though
+#   portions of the text of the Macro appear in them. The GNU General
+#   Public License (GPL) does govern all other use of the material that
+#   constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the
+#   Autoconf Macro released by the Autoconf Macro Archive. When you
+#   make and distribute a modified version of the Autoconf Macro, you
+#   may extend this special exception to the GPL to apply to your
+#   modified version as well.
+
+AC_DEFUN([AX_C_CHECK_FLAG],[
+# modification AE: require only 2.59; then we do not have AC_PROG_SED
+#  AC_PREREQ([2.61])
+  AC_PREREQ([2.59])
+  AC_REQUIRE([AC_PROG_CC])
+# modification AE
+#  AC_REQUIRE([AC_PROG_SED])
+#  flag=`echo "$1" | $SED 'y% .=/+-(){}<>:*,%_______________%'`
+  flag="_$1"
+
+  AC_CACHE_CHECK([whether the C compiler accepts the $1 flag],
+    [ax_cv_c_check_flag_$flag],[
+
+    AC_LANG_PUSH([C])
+
+    save_CFLAGS="$CFLAGS"
+# modification AE
+#    CFLAGS="$CFLAGS $1"
+    CFLAGS="$CFLAGS -$1"
+    AC_COMPILE_IFELSE([
+      AC_LANG_PROGRAM([$2],[$3])
+    ],[
+      eval "ax_cv_c_check_flag_$flag=yes"
+    ],[
+      eval "ax_cv_c_check_flag_$flag=no"
+    ])
+
+    CFLAGS="$save_CFLAGS"
+
+    AC_LANG_POP
+
+  ])
+
+  AS_IF([eval "test \"`echo '$ax_cv_c_check_flag_'$flag`\" = yes"],[
+   :
+    $4
+  ],[
+   :
+    $5
+  ])
+])
+
+
 #                                               -*- Autoconf -*-
 # Process this file with autoconf to produce a configure script.
 
@@ -9,8 +107,6 @@ AC_CONFIG_HEADER([config.h])
 AM_INIT_AUTOMAKE([1.9 -Wall -Werror])
 AM_MAINTAINER_MODE
 
-CFLAGS="-g -O2 -ansi -pedantic-errors -Wall -Wextra -Werror"
-
 dnl Extra arguments to configure
 AC_ARG_WITH([mpfr],
             [AC_HELP_STRING([--with-mpfr=DIR],
@@ -31,6 +127,13 @@ AC_ARG_WITH([gmp],
 AC_PROG_CC
 AC_PROG_LIBTOOL
 
+# Checks for CC flags.
+AX_C_CHECK_FLAG(ansi,,,CFLAGS="$CFLAGS -ansi",)
+AX_C_CHECK_FLAG(pedantic,,,CFLAGS="$CFLAGS -pedantic",)
+AX_C_CHECK_FLAG(Wall,,,CFLAGS="$CFLAGS -Wall",)
+AX_C_CHECK_FLAG(Wextra,,,CFLAGS="$CFLAGS -Wextra",)
+AX_C_CHECK_FLAG(Werror,,,CFLAGS="$CFLAGS -Werror",)
+
 # Checks for libraries.
 AC_CHECK_LIB([mpfr], [mpfr_clear],,
              [AC_MSG_ERROR([MPC library needs the MPFR library])])
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 096a06a..a66a3fc 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -2,7 +2,7 @@
 LDADD = $(top_builddir)/src/libmpc.la
 
 
-AM_CPPFLAGS = -I$(top_srcdir)/src -I$(top_srcdir)/tests
+AM_CPPFLAGS = -I$(top_srcdir)/src
 check_PROGRAMS = tadd test tcos tdiv texp tlog tmul tsin tsqr tsqrt tsub
 
 TESTS = $(check_PROGRAMS)