ax_cflags_warn_all
==================

Synopsis
********

     AX_CFLAGS_WARN_ALL   [(shellvar[, default[, action-if-found[, action-if-not-found]]])]
     AX_CXXFLAGS_WARN_ALL [(shellvar[, default[, action-if-found[, action-if-not-found]]])]
     AX_FCFLAGS_WARN_ALL  [(shellvar[, default[, action-if-found[, action-if-not-found]]])]

Description
***********

Specify compiler options that enable most reasonable warnings.  For the GNU Compiler Collection (GCC), for example, it will be "-Wall".  The result is added to shellvar, one of CFLAGS, CXXFLAGS or FCFLAGS if the first parameter is not specified.

Each of these macros accepts the following optional arguments:

       - $1 - shellvar
           shell variable to use (CFLAGS, CXXFLAGS or FCFLAGS if not
           specified, depending on macro)

       - $2 - default
           value to use for flags if compiler vendor cannot be determined (by
           default, "")

       - $3 - action-if-found
           action to take if the compiler vendor has been successfully
           determined (by default, add the appropriate compiler flags to
           shellvar)

       - $4 - action-if-not-found
           action to take if the compiler vendor has not been determined or
           is unknown (by default, add the default flags, or "" if not
           specified, to shellvar)

These macros use AX_COMPILER_VENDOR to determine which flags should be returned for a given compiler.  Not all compilers currently have flags defined for them; patches are welcome.  If need be, compiler flags may be made language-dependent: use a construct like the following:

       [vendor_name], [m4_if(_AC_LANG_PREFIX,[C],   VAR="--relevant-c-flags",dnl
                       m4_if(_AC_LANG_PREFIX,[CXX], VAR="--relevant-c++-flags",dnl
                       m4_if(_AC_LANG_PREFIX,[FC],  VAR="--relevant-fortran-flags",dnl
                       VAR="$2"; FOUND="no")))],

Note: These macros also depend on AX_PREPEND_FLAG.

Source Code
***********

Download the latest version of ax_cflags_warn_all.m4 (http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_cflags_warn_all.m4) or browse the macro's revision history (http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=history;f=m4/ax_cflags_warn_all.m4).

License
*******

Copyright © 2008 Guido U. Draheim guidod@gmx.de
 Copyright © 2010 Rhys Ulerich rhys.ulerich@gmail.com
 Copyright © 2018 John Zaitseff J.Zaitseff@zap.org.au

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 3 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, see <https://www.gnu.org/licenses/>.

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