From f17e0182b963c18281fcd4348b314f3f0dd4283a Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Sat, 3 Jan 2015 15:16:09 +0100 Subject: [PATCH] janus-gateway: add a patch to use -Wunused-but-set-variable only when available Fixes: http://autobuild.buildroot.org/results/3f0/3f07574e6e4edda9e31fcb0de520a4dbabe6b94a/ [Thomas: - Improved configure.ac logic, as suggested by Yann E. Morin. - Added a comment in the .mk file to indicate why we're using AUTORECONF = YES. Suggested by Yann as well.] Signed-off-by: Thomas Petazzoni --- ...dd-test-for-Wunused-but-set-variable.patch | 133 ++++++++++++++++++ package/janus-gateway/janus-gateway.mk | 3 +- 2 files changed, 135 insertions(+), 1 deletion(-) create mode 100644 package/janus-gateway/0002-Add-test-for-Wunused-but-set-variable.patch diff --git a/package/janus-gateway/0002-Add-test-for-Wunused-but-set-variable.patch b/package/janus-gateway/0002-Add-test-for-Wunused-but-set-variable.patch new file mode 100644 index 0000000000..14acae5575 --- /dev/null +++ b/package/janus-gateway/0002-Add-test-for-Wunused-but-set-variable.patch @@ -0,0 +1,133 @@ +From c0f075bdee5edabf8f19b68e0880fbd249a89653 Mon Sep 17 00:00:00 2001 +From: Thomas Petazzoni +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 +--- + Makefile.am | 2 +- + configure.ac | 3 ++ + m4/ax_check_compile_flag.m4 | 74 +++++++++++++++++++++++++++++++++++++++++++++ + 3 files changed, 78 insertions(+), 1 deletion(-) + create mode 100644 m4/ax_check_compile_flag.m4 + +diff --git a/Makefile.am b/Makefile.am +index 5d23e0b..0f51f6a 100644 +--- a/Makefile.am ++++ b/Makefile.am +@@ -6,7 +6,7 @@ AM_CFLAGS = \ + -Wnested-externs -Wstrict-prototypes -Wunsafe-loop-optimizations \ + -Wwrite-strings -Wno-missing-field-initializers -Wno-unused-parameter \ + -Wcast-align -Wformat-nonliteral -Wformat-security -Wswitch-default \ +- -Wmissing-include-dirs -Waggregate-return -Wunused-but-set-variable \ ++ -Wmissing-include-dirs -Waggregate-return @GCC_WARN_UNUSED_BUT_SET@ \ + -Warray-bounds -Wold-style-definition -Wsign-compare -Wlarger-than=65537 + AM_CFLAGS += -Wno-undef # sophiasip is not -Wundef--safe + AM_CFLAGS += -Wredundant-decls # sophiasip also contains redundant declarations +diff --git a/configure.ac b/configure.ac +index 17870a7..f9bb1e4 100644 +--- a/configure.ac ++++ b/configure.ac +@@ -7,6 +7,9 @@ AM_SILENT_RULES([yes]) + AC_GNU_SOURCE + + 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 +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 ++# Copyright (c) 2011 Maarten Bosmans ++# ++# 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 . ++# ++# 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 +-- +2.1.0 + diff --git a/package/janus-gateway/janus-gateway.mk b/package/janus-gateway/janus-gateway.mk index 6c89e9a0f3..d2556e0c25 100644 --- a/package/janus-gateway/janus-gateway.mk +++ b/package/janus-gateway/janus-gateway.mk @@ -13,7 +13,8 @@ JANUS_GATEWAY_LICENSE_FILES = COPYING JANUS_GATEWAY_DEPENDENCIES = host-pkgconf libmicrohttpd jansson \ libnice sofia-sip libsrtp host-gengetopt openssl ding-libs -# Straight out of the repository, no ./configure +# Straight out of the repository, no ./configure, and we also patch +# configure.ac. JANUS_GATEWAY_AUTORECONF = YES define JANUS_GATEWAY_M4