build: add and use global EXTRA_WARNINGS from common/Make.rules

Define EXTRA_WARNINGS in the common/Make.rules helper so that adding
additional warnings can be done in one(-ish) location, and replace
locally defined C compiler warning flags with EXTRA_WARNINGS in most
locations in the build tree.

v2: issue a warning for any compiler option that the compiler does not
    support

Signed-off-by: Steve Beattie <steve.beattie@canonical.com>

binutils/Makefile

@@ -24,7 +24,6 @@ LOCALEDIR=/usr/share/locale
 MANPAGES=aa-enabled.1 aa-exec.1 aa-status.8
 
 WARNINGS = -Wall
-EXTRA_WARNINGS = -Wsign-compare -Wmissing-field-initializers -Wformat -Wformat-security -Wunused-parameter
 CPP_WARNINGS =
 ifndef CFLAGS
 CFLAGS	= -g -O2 -pipe

changehat/mod_apparmor/Makefile

@@ -70,7 +70,7 @@ libapparmor by adding USE_SYSTEM=1 to your make command.${nl}\
   LDLIBS = -lapparmor
 endif
 
-APXS_CFLAGS="-Wc,-Wsign-compare -Wmissing-field-initializers -Wformat -Wformat-security -Wunused-parameter"
+APXS_CFLAGS="-Wc,$(EXTRA_WARNINGS)"
 
 .PHONY: libapparmor_check
 .SILENT: libapparmor_check

changehat/pam_apparmor/Makefile

@@ -54,7 +54,7 @@ libapparmor by adding USE_SYSTEM=1 to your make command.${nl}\
   AA_LINK_FLAGS = -L$(LIBAPPARMOR_PATH)
   AA_LDLIBS = -lapparmor
 endif
-EXTRA_CFLAGS=$(CFLAGS) $(CPPFLAGS) -fPIC -shared -Wall -Wsign-compare -Wmissing-field-initializers -Wformat -Wformat-security -Wunused-parameter $(LIBAPPARMOR_INCLUDE)
+EXTRA_CFLAGS=$(CFLAGS) $(CPPFLAGS) -fPIC -shared -Wall $(EXTRA_WARNINGS) $(LIBAPPARMOR_INCLUDE)
 LINK_FLAGS=-Xlinker -x $(AA_LINK_FLAGS) $(LDFLAGS)
 LIBS=-lpam $(AA_LDLIBS)
 OBJECTS=${NAME}.o get_options.o

common/Make.rules

@@ -57,6 +57,18 @@ endif
 #Helper function to be used with $(call pyalldo, run_test_with_all.py)
 pyalldo=set -e; $(foreach py, $(PYTHON_VERSIONS), $(py) $(1);)
 
+# Common set of compiler warnings
+_EXTRA_WARNINGS = -Wall -Wsign-compare -Wmissing-field-initializers -Wformat -Wformat-security -Wunused-parameter
+EXTRA_WARNINGS := $(shell for warning in ${_EXTRA_WARNINGS} ; do \
+			if ${CC} $${warning} -S -o /dev/null -xc /dev/null >/dev/null 2>&1; then \
+				echo "$${warning}"; \
+			else \
+				echo "***" >&2 ; \
+				echo "WARNING: unable to use $${warning} with ${CC}, dropping" >&2 ; \
+				echo "***" >&2 ; \
+			fi ; \
+		    done)
+
 .PHONY: version
 .SILENT: version
 version:

libraries/libapparmor/src/Makefile.am

@@ -32,10 +32,13 @@ AA_LIB_AGE = 6
 
 SUFFIXES = .pc.in .pc
 
+COMMONDIR=$(top_srcdir)/../../common/
+include $(COMMONDIR)/Make.rules
+
 BUILT_SOURCES = grammar.h scanner.h af_protos.h
 AM_LFLAGS = -v
 AM_YFLAGS = -d -p aalogparse_
-AM_CFLAGS = -Wall -Wsign-compare -Wmissing-field-initializers -Wformat -Wformat-security -Wunused-parameter -fPIC
+AM_CFLAGS = -Wall $(EXTRA_WARNINGS) -fPIC
 AM_CPPFLAGS = -D_GNU_SOURCE -I$(top_srcdir)/include/
 scanner.h: scanner.l
 	$(LEX) -v $<

libraries/libapparmor/swig/python/Makefile.am

@@ -1,5 +1,8 @@
 if HAVE_PYTHON
 
+COMMONDIR = $(top_srcdir)/../../common/
+include $(COMMONDIR)/Make.rules
+
 EXTRA_DIST      = libapparmor_wrap.c
 
 SUBDIRS = test
@@ -11,7 +14,7 @@ MOSTLYCLEANFILES=libapparmor_wrap.c LibAppArmor.py
 
 all-local: libapparmor_wrap.c setup.py
 	if test ! -f libapparmor_wrap.c; then cp $(srcdir)/libapparmor_wrap.c . ; fi
-	CC="$(CC)" CFLAGS="$(PYTHON_CPPFLAGS)" LDSHARED="$(CC) -shared" LDFLAGS="$(PYTHON_LDFLAGS)" $(PYTHON) setup.py build
+	CC="$(CC)" CFLAGS="$(PYTHON_CPPFLAGS) $(EXTRA_WARNINGS)" LDSHARED="$(CC) -shared" LDFLAGS="$(PYTHON_LDFLAGS)" $(PYTHON) setup.py build
 
 install-exec-local:
 	$(PYTHON) setup.py install --root="/$(DESTDIR)" --prefix="$(prefix)"

libraries/libapparmor/testsuite/Makefile.am

@@ -2,6 +2,9 @@ SUBDIRS = lib config libaalogparse.test
 PACKAGE = libaalogparse
 AUTOMAKE_OPTIONS = dejagnu
 
+COMMONDIR=$(top_srcdir)/../../common
+include $(COMMONDIR)/Make.rules
+
 INCLUDES = -I. -I$(top_srcdir)/include
 
 AM_CPPFLAGS = $(DEBUG_FLAGS) -DLOCALEDIR=\"${localedir}\"
@@ -10,7 +13,7 @@ AM_CFLAGS = -Wall
 noinst_PROGRAMS = test_multi.multi
 
 test_multi_multi_SOURCES	= test_multi.c
-test_multi_multi_CFLAGS		= -Wall
+test_multi_multi_CFLAGS		= -Wall $(EXTRA_WARNINGS)
 test_multi_multi_LDADD		= -L../src/.libs -lapparmor
 
 clean-local:

parser/Makefile

@@ -37,12 +37,7 @@ YFLAGS	:= -d
 LEX	:= flex
 LEXFLAGS = -B -v
 WARNINGS = -Wall
-EXTRA_WARNINGS = -Wsign-compare -Wmissing-field-initializers -Wformat -Wformat-security -Wunused-parameter
+CXX_WARNINGS = ${WARNINGS} ${EXTRA_WARNINGS}
-CXX_WARNINGS = ${WARNINGS} $(shell for warning in ${EXTRA_WARNINGS} ; do \
-			if ${CXX} $${warning} -S -o /dev/null -xc /dev/null >/dev/null 2>&1; then \
-				echo "$${warning}"; \
-			fi ; \
-		done)
 CPP_WARNINGS =
 ifndef CFLAGS
 CFLAGS	= -g -O2 -pipe

tests/regression/apparmor/Makefile

@@ -67,7 +67,7 @@ system aa-exec by adding USE_SYSTEM=1 to your make command.${nl}\
   LDLIBS += -Wl,-Bstatic -lapparmor -Wl,-Bdynamic -lpthread
 endif # USE_SYSTEM
 
-CFLAGS += -g -O0 -Wall -Wstrict-prototypes -Wsign-compare -Wmissing-field-initializers -Wformat -Wformat-security -Wunused-parameter
+CFLAGS += -g -O0 $(EXTRA_WARNINGS)
 
 SRC=access.c \
     at_secure.c \