[kvm-unit-tests v3 PATCH 2/3] Replace -Wextra with a saner list of warning flags

[Thomas Huth <thuth@redhat.com>]

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.
Since they apparently can be used for building x86, too, the flags
are now also applied to the global CFLAGS instead of specifying them
for the single targets only.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 Makefile                | 8 ++++++--
 arm/Makefile.common     | 1 -
 powerpc/Makefile.common | 1 -
 s390x/Makefile          | 1 -
 4 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/Makefile b/Makefile
index 3ef6ea7..97d6591 100644
--- a/Makefile
+++ b/Makefile
@@ -50,8 +50,10 @@ 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 ;)
 
-COMMON_CFLAGS += -g
-COMMON_CFLAGS += $(autodepend-flags) -Wall -Wwrite-strings -Werror
+COMMON_CFLAGS += -g $(autodepend-flags)
+COMMON_CFLAGS += -Wall -Wwrite-strings -Wclobbered -Wempty-body -Wuninitialized
+COMMON_CFLAGS += -Wtype-limits -Wignored-qualifiers -Wunused-but-set-parameter
+COMMON_CFLAGS += -Werror
 frame-pointer-flag=-f$(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, "")
@@ -67,6 +69,8 @@ COMMON_CFLAGS += $(if $(U32_LONG_FMT),-D__U32_LONG_FMT__,)
 COMMON_CFLAGS += $(fno_pic) $(no_pie)
 
 CFLAGS += $(COMMON_CFLAGS)
+CFLAGS += -Wmissing-parameter-type -Wold-style-declaration -Woverride-init
+
 CXXFLAGS += $(COMMON_CFLAGS)
 
 autodepend-flags = -MMD -MF $(dir $*).$(notdir $*).d
diff --git a/arm/Makefile.common b/arm/Makefile.common
index 03b497b..7e5f527 100644
--- a/arm/Makefile.common
+++ b/arm/Makefile.common
@@ -24,7 +24,6 @@ phys_base = $(LOADADDR)
 
 CFLAGS += -std=gnu99
 CFLAGS += -ffreestanding
-CFLAGS += -Wextra
 CFLAGS += -O2
 CFLAGS += -I $(SRCDIR)/lib -I $(SRCDIR)/lib/libfdt -I lib
 
diff --git a/powerpc/Makefile.common b/powerpc/Makefile.common
index db5ba62..c4df2e9 100644
--- a/powerpc/Makefile.common
+++ b/powerpc/Makefile.common
@@ -19,7 +19,6 @@ all: directories $(TEST_DIR)/boot_rom.bin $(tests-all)
 
 CFLAGS += -std=gnu99
 CFLAGS += -ffreestanding
-CFLAGS += -Wextra
 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..bc099da 100644
--- a/s390x/Makefile
+++ b/s390x/Makefile
@@ -7,7 +7,6 @@ test_cases: $(tests)
 
 CFLAGS += -std=gnu99
 CFLAGS += -ffreestanding
-CFLAGS += -Wextra
 CFLAGS += -I $(SRCDIR)/lib
 CFLAGS += -O2
 CFLAGS += -march=z900
-- 
1.8.3.1