123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146 |
- From c0f075bdee5edabf8f19b68e0880fbd249a89653 Mon Sep 17 00:00:00 2001
- From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
- Date: Sat, 3 Jan 2015 15:09:59 +0100
- Subject: [PATCH] Add test for -Wunused-but-set-variable
- The -Wunused-but-set-variable option does not exist in some old gcc
- versions (gcc 4.5.x), so using it unconditionally breaks the build
- with such compilers.
- This commit introduces the AX_CHECK_COMPILE_FLAG m4 macro taken from
- the autoconf-archive
- (http://git.savannah.gnu.org/gitweb/?p=autoconf-archive.git;a=blob_plain;f=m4/ax_check_compile_flag.m4),
- and uses it to detect if the -Wunused-but-set-variable option is
- supported, and only uses it in this case.
- Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
- (rebased against v0.1.0)
- Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
- (rebased against v0.6.3)
- Signed-off-by: Adam Duskett <Aduskett@gmail.com>
- ---
- Makefile.am | 1 +
- configure.ac | 6 ++-
- m4/ax_check_compile_flag.m4 | 74 +++++++++++++++++++++++++++++++++++++
- 3 files changed, 79 insertions(+), 2 deletions(-)
- create mode 100644 m4/ax_check_compile_flag.m4
- diff --git a/Makefile.am b/Makefile.am
- index f961fdb..3ddbe59 100644
- --- a/Makefile.am
- +++ b/Makefile.am
- @@ -151,6 +151,7 @@ janus_CFLAGS = \
- -DEVENTDIR=\"$(eventdir)\" \
- -DLOGGERDIR=\"$(loggerdir)\" \
- -DCONFDIR=\"$(confdir)\" \
- + @GCC_WARN_UNUSED_BUT_SET@ \
- $(BORINGSSL_CFLAGS) \
- $(NULL)
-
- diff --git a/configure.ac b/configure.ac
- index ca17a29..beef91a 100644
- --- a/configure.ac
- +++ b/configure.ac
- @@ -13,6 +13,9 @@ AM_SILENT_RULES([yes])
- AC_USE_SYSTEM_EXTENSIONS
-
- AC_PROG_CC
- +AX_CHECK_COMPILE_FLAG([-Wunused-but-set-variable],
- + [GCC_WARN_UNUSED_BUT_SET=-Wunused-but-set-variable])
- +AC_SUBST(GCC_WARN_UNUSED_BUT_SET)
-
- LT_PREREQ([2.2])
- LT_INIT
- @@ -64,8 +67,7 @@ clang*)
- CFLAGS="$CFLAGS \
- -Wcast-align \
- -Wno-override-init \
- - -Wunsafe-loop-optimizations \
- - -Wunused-but-set-variable"
- + -Wunsafe-loop-optimizations"
- esac
-
- JANUS_VERSION=103
- diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4
- new file mode 100644
- index 0000000..51df0c0
- --- /dev/null
- +++ b/m4/ax_check_compile_flag.m4
- @@ -0,0 +1,74 @@
- +# ===========================================================================
- +# http://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html
- +# ===========================================================================
- +#
- +# SYNOPSIS
- +#
- +# AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT])
- +#
- +# DESCRIPTION
- +#
- +# Check whether the given FLAG works with the current language's compiler
- +# or gives an error. (Warnings, however, are ignored)
- +#
- +# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on
- +# success/failure.
- +#
- +# If EXTRA-FLAGS is defined, it is added to the current language's default
- +# flags (e.g. CFLAGS) when the check is done. The check is thus made with
- +# the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to
- +# force the compiler to issue an error when a bad flag is given.
- +#
- +# INPUT gives an alternative input source to AC_COMPILE_IFELSE.
- +#
- +# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this
- +# macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG.
- +#
- +# LICENSE
- +#
- +# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de>
- +# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com>
- +#
- +# 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 <http://www.gnu.org/licenses/>.
- +#
- +# 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 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.
- +
- +#serial 3
- +
- +AC_DEFUN([AX_CHECK_COMPILE_FLAG],
- +[AC_PREREQ(2.59)dnl for _AC_LANG_PREFIX
- +AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
- +AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
- + ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
- + _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
- + AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])],
- + [AS_VAR_SET(CACHEVAR,[yes])],
- + [AS_VAR_SET(CACHEVAR,[no])])
- + _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])
- +AS_IF([test x"AS_VAR_GET(CACHEVAR)" = xyes],
- + [m4_default([$2], :)],
- + [m4_default([$3], :)])
- +AS_VAR_POPDEF([CACHEVAR])dnl
- +])dnl AX_CHECK_COMPILE_FLAGS
- --
- 2.20.1
|