diff --git a/Makefile b/Makefile index f97f786de58d..06e2b73978e8 100644 --- a/Makefile +++ b/Makefile @@ -370,7 +370,7 @@ LDFLAGS_MODULE = CFLAGS_KERNEL = AFLAGS_KERNEL = LDFLAGS_vmlinux = -CFLAGS_GCOV = -fprofile-arcs -ftest-coverage -fno-tree-loop-im +CFLAGS_GCOV = -fprofile-arcs -ftest-coverage -fno-tree-loop-im -Wno-maybe-uninitialized CFLAGS_KCOV := $(call cc-option,-fsanitize-coverage=trace-pc,) @@ -620,7 +620,6 @@ ARCH_CFLAGS := include arch/$(SRCARCH)/Makefile KBUILD_CFLAGS += $(call cc-option,-fno-delete-null-pointer-checks,) -KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,) KBUILD_CFLAGS += $(call cc-disable-warning,frame-address,) ifdef CONFIG_LD_DEAD_CODE_DATA_ELIMINATION @@ -629,15 +628,18 @@ KBUILD_CFLAGS += $(call cc-option,-fdata-sections,) endif ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE -KBUILD_CFLAGS += -Os +KBUILD_CFLAGS += -Os $(call cc-disable-warning,maybe-uninitialized,) else ifdef CONFIG_PROFILE_ALL_BRANCHES -KBUILD_CFLAGS += -O2 +KBUILD_CFLAGS += -O2 $(call cc-disable-warning,maybe-uninitialized,) else KBUILD_CFLAGS += -O2 endif endif +KBUILD_CFLAGS += $(call cc-ifversion, -lt, 0409, \ + $(call cc-disable-warning,maybe-uninitialized,)) + # Tell gcc to never replace conditional load with a non-conditional one KBUILD_CFLAGS += $(call cc-option,--param=allow-store-data-races=0) diff --git a/arch/arc/Makefile b/arch/arc/Makefile index 864adad52280..25f81a1db9f9 100644 --- a/arch/arc/Makefile +++ b/arch/arc/Makefile @@ -68,7 +68,9 @@ cflags-$(CONFIG_ARC_DW2_UNWIND) += -fasynchronous-unwind-tables $(cfi) ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE # Generic build system uses -O2, we want -O3 # Note: No need to add to cflags-y as that happens anyways -ARCH_CFLAGS += -O3 +# +# Disable the false maybe-uninitialized warings gcc spits out at -O3 +ARCH_CFLAGS += -O3 $(call cc-disable-warning,maybe-uninitialized,) endif # small data is default for elf32 tool-chain. If not usable, disable it diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn index 53449a6ff6aa..7fc2c5a3dbbe 100644 --- a/scripts/Makefile.extrawarn +++ b/scripts/Makefile.extrawarn @@ -36,6 +36,7 @@ warning-2 += -Wshadow warning-2 += $(call cc-option, -Wlogical-op) warning-2 += $(call cc-option, -Wmissing-field-initializers) warning-2 += $(call cc-option, -Wsign-compare) +warning-2 += $(call cc-option, -Wmaybe-uninitialized) warning-3 := -Wbad-function-cast warning-3 += -Wcast-qual @@ -59,6 +60,8 @@ endif KBUILD_CFLAGS += $(warning) else +KBUILD_CFLAGS += $(call cc-disable-warning, maybe-uninitialized) + ifeq ($(cc-name),clang) KBUILD_CFLAGS += $(call cc-disable-warning, initializer-overrides) KBUILD_CFLAGS += $(call cc-disable-warning, unused-value) diff --git a/scripts/Makefile.ubsan b/scripts/Makefile.ubsan index dd779c40c8e6..3b1b13818d59 100644 --- a/scripts/Makefile.ubsan +++ b/scripts/Makefile.ubsan @@ -17,4 +17,8 @@ endif ifdef CONFIG_UBSAN_NULL CFLAGS_UBSAN += $(call cc-option, -fsanitize=null) endif + + # -fsanitize=* options makes GCC less smart than usual and + # increase number of 'maybe-uninitialized false-positives + CFLAGS_UBSAN += $(call cc-option, -Wno-maybe-uninitialized) endif