From 3de6c5798b64f25e80e3f8d916e4e7a3aac5f68d Mon Sep 17 00:00:00 2001 From: Benno Schulenberg Date: Mon, 24 Mar 2014 13:31:37 +0000 Subject: [PATCH] Compiling with warnings enabled by default, to help prevent issues from silently creeping in. Patch by Mike Frysinger. git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@4671 35c25a1d-7b9e-4130-9fde-d3aeb78583b8 --- ChangeLog | 3 ++ configure.ac | 3 ++ m4/ax_check_compile_flag.m4 | 74 +++++++++++++++++++++++++++++++++++++ 3 files changed, 80 insertions(+) create mode 100644 m4/ax_check_compile_flag.m4 diff --git a/ChangeLog b/ChangeLog index 0fb6e2d5..b72847f2 100644 --- a/ChangeLog +++ b/ChangeLog @@ -4,6 +4,9 @@ * doc/syntax/javascript.nanorc - New file, by Mike Frysinger. * doc/syntax/{nanorc,python}.nanorc - Highlight trailing whitespace. Patches by Mike Frysinger . + * configure.ac, m4/ax_check_compile_flag.m4 - Start building + with warnings enabled by default, to help prevent issues from + silently creeping in. Patch by Mike Frysinger. 2014-03-23 Benno Schulenberg * src/rcfile.c (parse_keybinding, parse_unbinding) - Improve a diff --git a/configure.ac b/configure.ac index ee3ef716..85820b1e 100644 --- a/configure.ac +++ b/configure.ac @@ -431,6 +431,9 @@ fi dnl Checks for typedefs, structures, and compiler characteristics. +dnl Checks for available flags. +AX_CHECK_COMPILE_FLAG([-Wall], [CFLAGS="$CFLAGS -Wall"], [], []) + dnl Checks for library functions. AC_TYPE_SIGNAL AC_FUNC_VPRINTF diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4 new file mode 100644 index 00000000..51df0c09 --- /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