1From b0a64db90a24469e36978c748417ebe456b34d59 Mon Sep 17 00:00:00 2001 2From: Khem Raj <raj.khem@gmail.com> 3Date: Sat, 22 Apr 2017 11:54:57 -0700 4Subject: [PATCH] configure: Check for -Wno-error=format-truncation compiler 5 option 6 7If this option is supported by compiler then disable it ( gcc7+) 8Use -Werror to elevate the warning to an error in case compiler like clang 9which warn about unknown options but not error out unless asked for 10 11Fixes 12client.c:834:23: error: '%s' directive output may be truncated writing up to 1023 bytes into a region of size 1010 [-Werror=format-truncation=] 13 14Signed-off-by: Khem Raj <raj.khem@gmail.com> 15 16--- 17 configure.ac | 1 + 18 m4/ax_check_compile_flag.m4 | 74 +++++++++++++++++++++++++++++++++++++ 19 2 files changed, 75 insertions(+) 20 create mode 100644 m4/ax_check_compile_flag.m4 21 22diff --git a/configure.ac b/configure.ac 23index a7eca97d..560eb988 100644 24--- a/configure.ac 25+++ b/configure.ac 26@@ -6794,6 +6794,7 @@ if test "x$enable_werror" != "xno"; then 27 AM_CFLAGS="$AM_CFLAGS -Werror" 28 AM_CXXFLAGS="$AM_CXXFLAGS -Werror" 29 fi 30+AX_CHECK_COMPILE_FLAG([-Werror -Werror=format-truncation],[AM_CFLAGS="$AM_CFLAGS -Wno-error=format-truncation" AM_CXXFLAGS="$AM_CXXFLAGS -Wno-error=format-truncation"]) 31 32 AC_SUBST([AM_CFLAGS]) 33 AC_SUBST([AM_CXXFLAGS]) 34diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4 35new file mode 100644 36index 00000000..dcabb92a 37--- /dev/null 38+++ b/m4/ax_check_compile_flag.m4 39@@ -0,0 +1,74 @@ 40+# =========================================================================== 41+# https://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html 42+# =========================================================================== 43+# 44+# SYNOPSIS 45+# 46+# AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT]) 47+# 48+# DESCRIPTION 49+# 50+# Check whether the given FLAG works with the current language's compiler 51+# or gives an error. (Warnings, however, are ignored) 52+# 53+# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on 54+# success/failure. 55+# 56+# If EXTRA-FLAGS is defined, it is added to the current language's default 57+# flags (e.g. CFLAGS) when the check is done. The check is thus made with 58+# the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to 59+# force the compiler to issue an error when a bad flag is given. 60+# 61+# INPUT gives an alternative input source to AC_COMPILE_IFELSE. 62+# 63+# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this 64+# macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG. 65+# 66+# LICENSE 67+# 68+# Copyright (c) 2008 Guido U. Draheim <guidod@gmx.de> 69+# Copyright (c) 2011 Maarten Bosmans <mkbosmans@gmail.com> 70+# 71+# This program is free software: you can redistribute it and/or modify it 72+# under the terms of the GNU General Public License as published by the 73+# Free Software Foundation, either version 3 of the License, or (at your 74+# option) any later version. 75+# 76+# This program is distributed in the hope that it will be useful, but 77+# WITHOUT ANY WARRANTY; without even the implied warranty of 78+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 79+# Public License for more details. 80+# 81+# You should have received a copy of the GNU General Public License along 82+# with this program. If not, see <https://www.gnu.org/licenses/>. 83+# 84+# As a special exception, the respective Autoconf Macro's copyright owner 85+# gives unlimited permission to copy, distribute and modify the configure 86+# scripts that are the output of Autoconf when processing the Macro. You 87+# need not follow the terms of the GNU General Public License when using 88+# or distributing such scripts, even though portions of the text of the 89+# Macro appear in them. The GNU General Public License (GPL) does govern 90+# all other use of the material that constitutes the Autoconf Macro. 91+# 92+# This special exception to the GPL applies to versions of the Autoconf 93+# Macro released by the Autoconf Archive. When you make and distribute a 94+# modified version of the Autoconf Macro, you may extend this special 95+# exception to the GPL to apply to your modified version as well. 96+ 97+#serial 5 98+ 99+AC_DEFUN([AX_CHECK_COMPILE_FLAG], 100+[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF 101+AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl 102+AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [ 103+ ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS 104+ _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1" 105+ AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])], 106+ [AS_VAR_SET(CACHEVAR,[yes])], 107+ [AS_VAR_SET(CACHEVAR,[no])]) 108+ _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags]) 109+AS_VAR_IF(CACHEVAR,yes, 110+ [m4_default([$2], :)], 111+ [m4_default([$3], :)]) 112+AS_VAR_POPDEF([CACHEVAR])dnl 113+])dnl AX_CHECK_COMPILE_FLAGS 114