On 29/06/2017 17:40, Thomas Huth wrote: > Using -Wextra together with -Werror is troublesome - various versions > of GCC produce suspicious or even wrong warnings with -Wextra which > then become fatal errors with -Werror. For example, the current state > of the kvm-unit-tests does not compile anymore with GCC 4.8.1 for > s390x due to an inadequate -Wmissing-field-initializers warning. > That's annoying for users who just would like to compile the > kvm-unit-tests and cumbersome for the developers who have to work > around these problems in the source code. So let's replace -Wextra > by a saner lists of warning flags that are normally enabled by -Wextra. > Most of them are added to the architecture independent CFLAGS list, > so that x86 now benefits from these checks, too. The ones that > could not be added there are placed in the architecture specific > CFLAGS instead. > > Signed-off-by: Thomas Huth <thuth@xxxxxxxxxx> > --- > Makefile | 5 +++-- > arm/Makefile.common | 3 ++- > powerpc/Makefile.common | 3 ++- > s390x/Makefile | 3 ++- > 4 files changed, 9 insertions(+), 5 deletions(-) > > diff --git a/Makefile b/Makefile > index e79cf93..56d2fd7 100644 > --- a/Makefile > +++ b/Makefile > @@ -50,8 +50,9 @@ include $(SRCDIR)/$(TEST_DIR)/Makefile > cc-option = $(shell if $(CC) $(1) -S -o /dev/null -xc /dev/null \ > > /dev/null 2>&1; then echo "$(1)"; else echo "$(2)"; fi ;) > > -CFLAGS += -g > -CFLAGS += $(autodepend-flags) -Wall -Wwrite-strings -Werror > +CFLAGS += -g $(autodepend-flags) > +CFLAGS += -Wall -Wwrite-strings -Wclobbered -Wempty-body -Wignored-qualifiers > +CFLAGS += -Wtype-limits -Wuninitialized -Wunused-but-set-parameter -Werror > frame-pointer-flag=-f$(if $(KEEP_FRAME_POINTER),no-,)omit-frame-pointer > fomit_frame_pointer := $(call cc-option, $(frame-pointer-flag), "") > fnostack_protector := $(call cc-option, -fno-stack-protector, "") > diff --git a/arm/Makefile.common b/arm/Makefile.common > index 03b497b..2840c2a 100644 > --- a/arm/Makefile.common > +++ b/arm/Makefile.common > @@ -24,7 +24,8 @@ phys_base = $(LOADADDR) > > CFLAGS += -std=gnu99 > CFLAGS += -ffreestanding > -CFLAGS += -Wextra > +CFLAGS += -Wmissing-parameter-type -Wold-style-declaration -Woverride-init > +CFLAGS += -Wsign-compare > CFLAGS += -O2 > CFLAGS += -I $(SRCDIR)/lib -I $(SRCDIR)/lib/libfdt -I lib > > diff --git a/powerpc/Makefile.common b/powerpc/Makefile.common > index db5ba62..50c4b24 100644 > --- a/powerpc/Makefile.common > +++ b/powerpc/Makefile.common > @@ -19,7 +19,8 @@ all: directories $(TEST_DIR)/boot_rom.bin $(tests-all) > > CFLAGS += -std=gnu99 > CFLAGS += -ffreestanding > -CFLAGS += -Wextra > +CFLAGS += -Wmissing-parameter-type -Wold-style-declaration -Woverride-init > +CFLAGS += -Wsign-compare > CFLAGS += -O2 > CFLAGS += -I $(SRCDIR)/lib -I $(SRCDIR)/lib/libfdt -I lib > CFLAGS += -Wa,-mregnames > diff --git a/s390x/Makefile b/s390x/Makefile > index 470cbba..3b8f5d9 100644 > --- a/s390x/Makefile > +++ b/s390x/Makefile > @@ -7,7 +7,8 @@ test_cases: $(tests) > > CFLAGS += -std=gnu99 > CFLAGS += -ffreestanding > -CFLAGS += -Wextra > +CFLAGS += -Wmissing-parameter-type -Wold-style-declaration -Woverride-init > +CFLAGS += -Wsign-compare > CFLAGS += -I $(SRCDIR)/lib > CFLAGS += -O2 > CFLAGS += -march=z900 I am not sure about -Wsign-compare, which can have a lot of false positives. Other opinions? x86 cannot use "Wmissing-parameter-type -Wold-style-declaration -Woverride-init" only because they're not valid in C++. Maybe we should split CFLAGS into COMMON_CCFLAGS and CFLAGS proper, so that CXXFLAGS and LDFLAGS can be assigned with CXXFLAGS += $(COMMON_CCFLAGS) LDFLAGS += $(COMMON_CCFLAGS) Then those three could go in CFLAGS, and the others in COMMON_CCFLAGS. Thanks, Paolo
