build-sys: do not set CFLAGS directly

Set a separate variable for adding warning flags. Build systems are not
supposed to change CFLAGS and LDFLAGS, these are user variables.

Reference: http://www.gnu.org/software/automake/manual/html_node/Flag-Variables-Ordering.html

diff --git a/Makefile.am b/Makefile.am
index 99ad9c03098cc3c89dd2d87f4920eae6440c6363..2699e594c37c2f66cd39bf694e48e03463018273 100644 (file)
--- a/Makefile.am
+++ b/Makefile.am
@@ -106,6 +106,8 @@ AM_CPPFLAGS = \
        -I $(top_srcdir)/src/journal \
        -I $(top_srcdir)/src/systemd
 
        -I $(top_srcdir)/src/journal \
        -I $(top_srcdir)/src/systemd
 

+AM_CFLAGS = $(WARNINGFLAGS)
+

 if TARGET_GENTOO
 AM_CPPFLAGS += \
        -DKBD_LOADKEYS=\"/usr/bin/loadkeys\" \
 if TARGET_GENTOO
 AM_CPPFLAGS += \
        -DKBD_LOADKEYS=\"/usr/bin/loadkeys\" \

diff --git a/configure.ac b/configure.ac
index 47a08dda6462f16c74b2dda5266b678bc6cf6b85..ac56bc717612bdffa5d8a513321acf6905225dfa 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -60,7 +60,7 @@ if test -z "$GPERF" ; then
         AC_MSG_ERROR([*** gperf not found])
 fi
 
         AC_MSG_ERROR([*** gperf not found])
 fi
 

-CC_CHECK_CFLAGS_APPEND([ \
+CC_CHECK_FLAGS_APPEND([with_cflags], [CFLAGS], [\

         -pipe \
         -Wall \
         -W \
         -pipe \
         -Wall \
         -W \


@@ -105,6 +105,7 @@ CC_CHECK_CFLAGS_APPEND([ \
         -fdata-sections \
         -Wl,--as-needed \
         -Wl,--gc-sections])
         -fdata-sections \
         -Wl,--as-needed \
         -Wl,--gc-sections])

+AC_SUBST([WARNINGFLAGS], $with_cflags)

 
 LT_PREREQ(2.2)
 LT_INIT
 
 LT_PREREQ(2.2)
 LT_INIT

diff --git a/m4/attributes.m4 b/m4/attributes.m4
index 9d561c244bf81ac321774905132ab61e01b4730a..e354375e349a385b7b8e70dd29f10a5ba2d6abe3 100644 (file)
--- a/m4/attributes.m4
+++ b/m4/attributes.m4
@@ -1,6 +1,7 @@
 dnl Macros to check the presence of generic (non-typed) symbols.
 dnl Copyright (c) 2006-2008 Diego Pettenò <flameeyes@gmail.com>
 dnl Copyright (c) 2006-2008 xine project
 dnl Macros to check the presence of generic (non-typed) symbols.
 dnl Copyright (c) 2006-2008 Diego Pettenò <flameeyes@gmail.com>
 dnl Copyright (c) 2006-2008 xine project

+dnl Copyright (c) 2012 Lucas De Marchi <lucas.de.marchi@gmail.com>

 dnl
 dnl This program is free software; you can redistribute it and/or modify
 dnl it under the terms of the GNU General Public License as published by
 dnl
 dnl This program is free software; you can redistribute it and/or modify
 dnl it under the terms of the GNU General Public License as published by


@@ -32,52 +33,28 @@ dnl distribute a modified version of the Autoconf Macro, you may extend
 dnl this special exception to the GPL to apply to your modified version as
 dnl well.
 
 dnl this special exception to the GPL to apply to your modified version as
 dnl well.
 

-dnl Check if the flag is supported by compiler
-dnl CC_CHECK_CFLAGS_SILENT([FLAG], [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
-
-AC_DEFUN([CC_CHECK_CFLAGS_SILENT], [
-  AC_CACHE_VAL(AS_TR_SH([cc_cv_cflags_$1]),
-    [ac_save_CFLAGS="$CFLAGS"
-     CFLAGS="$CFLAGS $1"
-     AC_COMPILE_IFELSE([AC_LANG_SOURCE([int a;])],
-       [eval "AS_TR_SH([cc_cv_cflags_$1])='yes'"],
-       [eval "AS_TR_SH([cc_cv_cflags_$1])='no'"])
-     CFLAGS="$ac_save_CFLAGS"
-    ])
-
-  AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
-    [$2], [$3])
-])
-
-dnl Check if the flag is supported by compiler (cacheable)
-dnl CC_CHECK_CFLAGS([FLAG], [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
-
-AC_DEFUN([CC_CHECK_CFLAGS], [
-  AC_CACHE_CHECK([if $CC supports $1 flag],
-    AS_TR_SH([cc_cv_cflags_$1]),
-    CC_CHECK_CFLAGS_SILENT([$1]) dnl Don't execute actions here!
-  )
-
-  AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
-    [$2], [$3])
-])
-
-dnl CC_CHECK_CFLAG_APPEND(FLAG, [action-if-found], [action-if-not-found])
-dnl Check for CFLAG and appends them to CFLAGS if supported
-AC_DEFUN([CC_CHECK_CFLAG_APPEND], [
-  AC_CACHE_CHECK([if $CC supports $1 flag],
-    AS_TR_SH([cc_cv_cflags_$1]),
-    CC_CHECK_CFLAGS_SILENT([$1]) dnl Don't execute actions here!
-  )
-
-  AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
-    [CFLAGS="$CFLAGS $1"; DEBUG_CFLAGS="$DEBUG_CFLAGS $1"; $2], [$3])
+dnl Check if FLAG in ENV-VAR is supported by compiler and append it
+dnl to WHERE-TO-APPEND variable
+dnl CC_CHECK_FLAG_APPEND([WHERE-TO-APPEND], [ENV-VAR], [FLAG])
+
+AC_DEFUN([CC_CHECK_FLAG_APPEND], [
+  AC_CACHE_CHECK([if $CC supports flag $3 in envvar $2],
+                 AS_TR_SH([cc_cv_$2_$3]),
+                [eval "AS_TR_SH([cc_save_$2])='${$2}'"
+                 eval "AS_TR_SH([$2])='$3'"
+                 AC_COMPILE_IFELSE([AC_LANG_SOURCE([int a = 0; int main(void) { return a; } ])],
+                                    [eval "AS_TR_SH([cc_cv_$2_$3])='yes'"],
+                                    [eval "AS_TR_SH([cc_cv_$2_$3])='no'"])
+                 eval "AS_TR_SH([$2])='$cc_save_$2'"])
+
+  AS_IF([eval test x$]AS_TR_SH([cc_cv_$2_$3])[ = xyes],
+        [eval "$1='${$1} $3'"])

 ])
 
 ])
 

-dnl CC_CHECK_CFLAGS_APPEND([FLAG1 FLAG2], [action-if-found], [action-if-not])
-AC_DEFUN([CC_CHECK_CFLAGS_APPEND], [
-  for flag in $1; do
-    CC_CHECK_CFLAG_APPEND($flag, [$2], [$3])
+dnl CC_CHECK_FLAGS_APPEND([WHERE-TO-APPEND], [ENV-VAR], [FLAG1 FLAG2])
+AC_DEFUN([CC_CHECK_FLAGS_APPEND], [
+  for flag in $3; do
+    CC_CHECK_FLAG_APPEND($1, $2, $flag)

   done
 ])
 
   done
 ])