build: cleanup and simplify flags handling

The ruby headers use some idioms which generate warnings when building paludis.
Rather than assuming that the associated -Wno-* flags are supported by the
compiler frontend, explicitly check for the support when necessary (building the
Ruby bindings).  This slightly speeds up the build when ruby is disabled, but
more importantly, will prevent the accidental usage of these flags more broadly.

6 files changed, 17 insertions, 46 deletions

diff --git a/configure.ac b/configure.ac
index 68ce726c7..e3c6d55e7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -31,6 +31,7 @@ AM_INIT_AUTOMAKE
 AC_LANG([C++])
 
 PALUDIS_CXXFLAGS=
+PALUDIS_RUBY_CXXFLAGS=
 
 dnl {{{ git revision
 if test -d "${GIT_DIR:-${ac_top_srcdir:-./}/.git}" ; then
@@ -306,13 +307,6 @@ int main(int, char **)
 AC_SUBST([PTHREAD_LIBS])
 AC_SUBST([RT_LIBS])
 
-PALUDIS_CXXFLAGS_NO_WOLD_STYLE_CAST=
-PALUDIS_CXXFLAGS_NO_WREDUNDANT_DECLS=
-PALUDIS_CXXFLAGS_NO_WSHADOW=
-PALUDIS_CXXFLAGS_NO_WUNUSED=
-PALUDIS_CXXFLAGS_NO_WEXTRA=
-PALUDIS_CXXFLAGS_NO_WWRITE_STRINGS=
-PALUDIS_CXXFLAGS_NO_WMISSING_NORETURN=
 PALUDIS_CXXFLAGS_NO_STRICT_ALIASING=
 
 AC_DEFUN([CHECK_CXXFLAG], [
@@ -340,42 +334,23 @@ int main(int, char **)
 if test "x${ac_cv_cxx_compiler_gnu}" = "xyes" ; then
 	CHECK_CXXFLAG([-Wall])
 	CHECK_CXXFLAG([-Wextra])
-	if ! test "x$cxxflag_success" = "xyes" ; then
+	if test x"$cxxflag_success" = x"no" ; then
 		CHECK_CXXFLAG([-W])
-	else
-		PALUDIS_CXXFLAGS_NO_WEXTRA=-Wno-extra
 	fi
 	CHECK_CXXFLAG([-Wold-style-cast])
-	if test "x$cxxflag_success" = "xyes" ; then
-		PALUDIS_CXXFLAGS_NO_WOLD_STYLE_CAST=-Wno-old-style-cast
-	fi
 	CHECK_CXXFLAG([-Wredundant-decls])
-	if test "x$cxxflag_success" = "xyes" ; then
-		PALUDIS_CXXFLAGS_NO_WREDUNDANT_DECLS=-Wno-redundant-decls
-	fi
 	CHECK_CXXFLAG([-Wstrict-null-sentinel])
 	CHECK_CXXFLAG([-Wmissing-noreturn])
-	if test "x$cxxflag_success" = "xyes" ; then
-		PALUDIS_CXXFLAGS_NO_WMISSING_NORETURN=-Wno-missing-noreturn
-	fi
 	CHECK_CXXFLAG([-Woverloaded-virtual])
 	CHECK_CXXFLAG([-Winit-self])
 	CHECK_CXXFLAG([-Wunreachable-code])
 	CHECK_CXXFLAG([-Wunused])
-	if test "x$cxxflag_success" = "xyes" ; then
-		PALUDIS_CXXFLAGS_NO_WUNUSED=-Wno-unused
-	fi
 	CHECK_CXXFLAG([-Wunused-function])
 	CHECK_CXXFLAG([-Wshadow])
-	if test "x$cxxflag_success" = "xyes" ; then
-		PALUDIS_CXXFLAGS_NO_WSHADOW=-Wno-shadow
-	fi
 	CHECK_CXXFLAG([-Wwrite-strings])
 	CHECK_CXXFLAG([-Wsignature-shadow])
 	CHECK_CXXFLAG([-Wfloat-equal])
-	if test "x$cxxflag_success" = "xyes" ; then
-		PALUDIS_CXXFLAGS_NO_WWRITE_STRINGS=-Wno-write-strings
-	fi
+
 	CHECK_CXXFLAG([-Wno-ignored-qualifiers])
 	CHECK_CXXFLAG([-Wno-non-virtual-dtor])
 else
@@ -392,13 +367,6 @@ CHECK_CXXFLAG([-fvisibility=hidden])
 CHECK_CXXFLAG([-fvisibility-inlines-hidden])
 
 AC_SUBST([PALUDIS_CXXFLAGS])
-AC_SUBST([PALUDIS_CXXFLAGS_NO_WOLD_STYLE_CAST])
-AC_SUBST([PALUDIS_CXXFLAGS_NO_WSHADOW])
-AC_SUBST([PALUDIS_CXXFLAGS_NO_WREDUNDANT_DECLS])
-AC_SUBST([PALUDIS_CXXFLAGS_NO_WEXTRA])
-AC_SUBST([PALUDIS_CXXFLAGS_NO_WUNUSED])
-AC_SUBST([PALUDIS_CXXFLAGS_NO_WWRITE_STRINGS])
-AC_SUBST([PALUDIS_CXXFLAGS_NO_WMISSING_NORETURN])
 
 save_CXXFLAGS="$CXXFLAGS"
 CXXFLAGS="$CXXFLAGS $PALUDIS_CXXFLAGS"
@@ -724,6 +692,16 @@ if test "x$enable_ruby" = "xyes" ; then
 
 	AC_SUBST([RUBY])
 	AC_SUBST([RUBY_INSTALL_DIR])
+
+	ruby_saved_CXXFLAGS="$CXXFLAGS"
+	ruby_saved_PALUDIS_CXXFLAGS="$PALUDIS_CXXFLAGS"
+	CHECK_CXXFLAG([-Wno-shadow])
+	CHECK_CXXFLAG([-Wno-redundant-decls])
+	CHECK_CXXFLAG([-Wno-old-style-cast])
+	PALUDIS_RUBY_CXXFLAGS="$PALUDIS_CXXFLAGS"
+	AC_SUBST([PALUDIS_RUBY_CXXFLAGS])
+	CXXFLAGS="$ruby_saved_CXXFLAGS"
+	PALUDIS_CXXFLAGS="$ruby_saved_PALUDIS_CXXFLAGS"
 fi
 AM_CONDITIONAL([ENABLE_RUBY], test "x$enable_ruby" = "xyes")
 dnl }}}
diff --git a/paludis/Makefile.am.m4 b/paludis/Makefile.am.m4
index bfc6ecd42..72c1af18d 100644
--- a/paludis/Makefile.am.m4
+++ b/paludis/Makefile.am.m4
@@ -50,7 +50,7 @@ ifelse(`$2', `testscript', `addtestscript(`$1')', `')')dnl
 define(`add', `addthis(`$1',`$2')addthis(`$1',`$3')addthis(`$1',`$4')dnl
 addthis(`$1',`$5')addthis(`$1',`$6')addthis(`$1',`$7')addthis(`$1',`$8')')dnl
 
-AM_CXXFLAGS = -I$(top_srcdir) @PALUDIS_CXXFLAGS@ @PALUDIS_CXXFLAGS_NO_WOLD_STYLE_CAST@
+AM_CXXFLAGS = -I$(top_srcdir) @PALUDIS_CXXFLAGS@
 
 include(`paludis/files.m4')
 
@@ -75,7 +75,6 @@ libpaludis_@PALUDIS_PC_SLOT@_la_LDFLAGS = -version-info @VERSION_LIB_CURRENT@:@V
 libpaludispythonhooks_@PALUDIS_PC_SLOT@_la_SOURCES = python_hooks.cc
 libpaludispythonhooks_@PALUDIS_PC_SLOT@_la_CXXFLAGS = $(AM_CXXFLAGS) \
 	@PALUDIS_CXXFLAGS_NO_STRICT_ALIASING@ \
-	@PALUDIS_CXXFLAGS_NO_WSHADOW@ \
 	-I@PYTHON_INCLUDE_DIR@
 libpaludispythonhooks_@PALUDIS_PC_SLOT@_la_LDFLAGS = -version-info @VERSION_LIB_CURRENT@:@VERSION_LIB_REVISION@:0 @BOOST_PYTHON_LIB@ -lpython@PYTHON_VERSION@
 libpaludispythonhooks_@PALUDIS_PC_SLOT@_la_LIBADD = libpaludis_@PALUDIS_PC_SLOT@.la
diff --git a/paludis/util/Makefile.am.m4 b/paludis/util/Makefile.am.m4
index fc41c0b05..bc4f550b4 100644
--- a/paludis/util/Makefile.am.m4
+++ b/paludis/util/Makefile.am.m4
@@ -48,7 +48,7 @@ ifelse(`$2', `testscript', `addtestscript(`$1')', `')')dnl
 define(`add', `addthis(`$1',`$2')addthis(`$1',`$3')addthis(`$1',`$4')dnl
 addthis(`$1',`$5')addthis(`$1',`$6')addthis(`$1',`$7')addthis(`$1',`$8')')dnl
 
-AM_CXXFLAGS = -I$(top_srcdir) @PALUDIS_CXXFLAGS@ @PALUDIS_CXXFLAGS_NO_WOLD_STYLE_CAST@
+AM_CXXFLAGS = -I$(top_srcdir) @PALUDIS_CXXFLAGS@
 
 include(`paludis/util/files.m4')
 
diff --git a/python/Makefile.am b/python/Makefile.am
index 9dff4f873..92a145f0e 100644
--- a/python/Makefile.am
+++ b/python/Makefile.am
@@ -5,12 +5,6 @@ SUBDIRS = .
 AM_CXXFLAGS = -I$(top_srcdir) -I$(srcdir)/ \
 	      -I$(top_builddir)/ \
 	      @PALUDIS_CXXFLAGS@ \
-	      @PALUDIS_CXXFLAGS_NO_WUNUSED@ \
-	      @PALUDIS_CXXFLAGS_NO_WSHADOW@ \
-	      @PALUDIS_CXXFLAGS_NO_WEXTRA@ \
-	      @PALUDIS_CXXFLAGS_NO_WOLD_STYLE_CAST@ \
-	      @PALUDIS_CXXFLAGS_NO_WWRITE_STRINGS@ \
-	      @PALUDIS_CXXFLAGS_NO_WMISSING_NORETURN@ \
 	      @PALUDIS_CXXFLAGS_NO_STRICT_ALIASING@ \
 	      @PALUDIS_CXXFLAGS_NO_DEBUGGING@
 
diff --git a/ruby/Makefile.am b/ruby/Makefile.am
index 06655d038..66fd38c97 100644
--- a/ruby/Makefile.am
+++ b/ruby/Makefile.am
@@ -4,7 +4,7 @@ SUBDIRS = . demos
 
 AM_CXXFLAGS = -I$(top_srcdir) -I$(srcdir)/ \
 	      -I$(top_builddir)/ \
-	      @PALUDIS_CXXFLAGS@
+	      @PALUDIS_RUBY_CXXFLAGS@
 
 DEFS= \
 	-DSYSCONFDIR=\"$(sysconfdir)\" \
diff --git a/src/clients/cave/Makefile.am b/src/clients/cave/Makefile.am
index 8489c68a1..75db797a2 100644
--- a/src/clients/cave/Makefile.am
+++ b/src/clients/cave/Makefile.am
@@ -1,7 +1,7 @@
 include $(top_srcdir)/misc/common-makefile.am
 
 AM_CXXFLAGS = -I$(top_srcdir) -I$(top_srcdir)/src \
-	      @PALUDIS_CXXFLAGS@ @PALUDIS_CXXFLAGS_NO_WOLD_STYLE_CAST@
+	      @PALUDIS_CXXFLAGS@
 DEFS= \
 	-DBINDIR=\"$(bindir)\" \
 	-DSYSCONFDIR=\"$(sysconfdir)\" \