When a Makefile variable is set on the make command line, all Makefile-internal assignments to that very variable are _ignored_. Since we add quite some essential values to CFLAGS internally, specifying some CFLAGS on the command line will usually break the build (and not fix any include file problems you hoped to overcome with that). Somewhat against intuition GNU make provides the "override" directive to change this behavior; with that assignments in the Makefile get _appended_ to the value given on the command line. [1] Change any internal assignments to use that directive, so that a user can use: $ make CFLAGS=/path/to/my/include/dir to teach kvmtool about non-standard header file locations (helpful for cross-compilation) or to tweak other compiler options. Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx> [1] https://www.gnu.org/software/make/manual/html_node/Override-Directive.html --- Makefile | 15 +++++++-------- 1 file changed, 7 insertions(+), 8 deletions(-) diff --git a/Makefile b/Makefile index f8f7cc4..77a7c9f 100644 --- a/Makefile +++ b/Makefile @@ -15,9 +15,7 @@ include config/utilities.mak include config/feature-tests.mak CC := $(CROSS_COMPILE)gcc -CFLAGS := LD := $(CROSS_COMPILE)ld -LDFLAGS := FIND := find CSCOPE := cscope @@ -162,7 +160,7 @@ ifeq ($(ARCH), arm) OBJS += arm/aarch32/kvm-cpu.o ARCH_INCLUDE := $(HDRS_ARM_COMMON) ARCH_INCLUDE += -Iarm/aarch32/include - CFLAGS += -march=armv7-a + override CFLAGS += -march=armv7-a ARCH_WANT_LIBFDT := y endif @@ -274,12 +272,12 @@ endif ifeq ($(LTO),1) FLAGS_LTO := -flto ifeq ($(call try-build,$(SOURCE_HELLO),$(CFLAGS),$(FLAGS_LTO)),y) - CFLAGS += $(FLAGS_LTO) + override CFLAGS += $(FLAGS_LTO) endif endif ifeq ($(call try-build,$(SOURCE_STATIC),,-static),y) - CFLAGS += -DCONFIG_GUEST_INIT + override CFLAGS += -DCONFIG_GUEST_INIT GUEST_INIT := guest/init GUEST_OBJS = guest/guest_init.o ifeq ($(ARCH_PRE_INIT),) @@ -331,7 +329,8 @@ DEFINES += -DKVMTOOLS_VERSION='"$(KVMTOOLS_VERSION)"' DEFINES += -DBUILD_ARCH='"$(ARCH)"' KVM_INCLUDE := include -CFLAGS += $(CPPFLAGS) $(DEFINES) -I$(KVM_INCLUDE) -I$(ARCH_INCLUDE) -O2 -fno-strict-aliasing -g +override CFLAGS += $(CPPFLAGS) $(DEFINES) -I$(KVM_INCLUDE) -I$(ARCH_INCLUDE) +override CFLAGS += -O2 -fno-strict-aliasing -g WARNINGS += -Wall WARNINGS += -Wformat=2 @@ -349,10 +348,10 @@ WARNINGS += -Wvolatile-register-var WARNINGS += -Wwrite-strings WARNINGS += -Wno-format-nonliteral -CFLAGS += $(WARNINGS) +override CFLAGS += $(WARNINGS) ifneq ($(WERROR),0) - CFLAGS += -Werror + override CFLAGS += -Werror endif all: $(PROGRAM) $(PROGRAM_ALIAS) $(GUEST_INIT) $(GUEST_PRE_INIT) -- 2.5.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
