This config option should be enabled only when both the compiler and the linker support necessary flags. Add proper dependencies to Kconfig. Unlike 'select', 'imply' is modest enough to observe those dependencies. I suggested this in the help message. Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> --- Changes in v3: None Changes in v2: None Makefile | 8 ++------ arch/Kconfig | 4 +++- 2 files changed, 5 insertions(+), 7 deletions(-) diff --git a/Makefile b/Makefile index 88733b7..92db767 100644 --- a/Makefile +++ b/Makefile @@ -754,8 +754,8 @@ KBUILD_CFLAGS += $(call cc-option, -fno-inline-functions-called-once) endif ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION -KBUILD_CFLAGS += $(call cc-option,-ffunction-sections,) -KBUILD_CFLAGS += $(call cc-option,-fdata-sections,) +KBUILD_CFLAGS += -ffunction-sections -fdata-sections +LDFLAGS_vmlinux += --gc-sections endif # arch Makefile may override CC so keep this after arch Makefile is included @@ -819,10 +819,6 @@ LDFLAGS_BUILD_ID := $(call ld-option, --build-id) KBUILD_LDFLAGS_MODULE += $(LDFLAGS_BUILD_ID) LDFLAGS_vmlinux += $(LDFLAGS_BUILD_ID) -ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION -LDFLAGS_vmlinux += $(call ld-option, --gc-sections,) -endif - ifeq ($(CONFIG_STRIP_ASM_SYMS),y) LDFLAGS_vmlinux += $(call ld-option, -X,) endif diff --git a/arch/Kconfig b/arch/Kconfig index 95b9b2e..e88f1ba 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -597,8 +597,10 @@ config CC_STACKPROTECTOR_STRONG config LD_DEAD_CODE_DATA_ELIMINATION bool + depends on $(cc-option -ffunction-sections -fdata-sections) + depends on $(ld-option --gc-sections) help - Select this if the architecture wants to do dead code and + Imply this if the architecture wants to do dead code and data elimination with the linker by compiling with -ffunction-sections -fdata-sections and linking with --gc-sections. -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
