diff options
| -rw-r--r-- | Makefile | 10 | ||||
| -rw-r--r-- | init/Kconfig | 17 | ||||
| -rw-r--r-- | kernel/trace/Kconfig | 1 |
3 files changed, 21 insertions, 7 deletions
@@ -660,17 +660,13 @@ KBUILD_CFLAGS += $(call cc-disable-warning, int-in-bool-context) ifdef CONFIG_CC_OPTIMIZE_FOR_SIZE KBUILD_CFLAGS += $(call cc-option,-Oz,-Os) -KBUILD_CFLAGS += $(call cc-disable-warning,maybe-uninitialized,) -else -ifdef CONFIG_PROFILE_ALL_BRANCHES -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,)) +ifdef CONFIG_CC_DISABLE_WARN_MAYBE_UNINITIALIZED +KBUILD_CFLAGS += -Wno-maybe-uninitialized +endif # 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/init/Kconfig b/init/Kconfig index 513fa544a134..ce43083b681d 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -26,6 +26,22 @@ config CLANG_VERSION config CC_HAS_ASM_GOTO def_bool $(success,$(srctree)/scripts/gcc-goto.sh $(CC)) +config CC_HAS_WARN_MAYBE_UNINITIALIZED + def_bool $(cc-option,-Wmaybe-uninitialized) + help + GCC >= 4.7 supports this option. + +config CC_DISABLE_WARN_MAYBE_UNINITIALIZED + bool + depends on CC_HAS_WARN_MAYBE_UNINITIALIZED + default CC_IS_GCC && GCC_VERSION < 40900 # unreliable for GCC < 4.9 + help + GCC's -Wmaybe-uninitialized is not reliable by definition. + Lots of false positive warnings are produced in some cases. + + If this option is enabled, -Wno-maybe-uninitialzed is passed + to the compiler to suppress maybe-uninitialized warnings. + config CONSTRUCTORS bool depends on !UML @@ -1102,6 +1118,7 @@ config CC_OPTIMIZE_FOR_PERFORMANCE config CC_OPTIMIZE_FOR_SIZE bool "Optimize for size" + imply CC_DISABLE_WARN_MAYBE_UNINITIALIZED # avoid false positives help Enabling this option will pass "-Os" instead of "-O2" to your compiler resulting in a smaller kernel. diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index fa8b1fe824f3..8bd1d6d001d7 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -370,6 +370,7 @@ config PROFILE_ANNOTATED_BRANCHES config PROFILE_ALL_BRANCHES bool "Profile all if conditionals" if !FORTIFY_SOURCE select TRACE_BRANCH_PROFILING + imply CC_DISABLE_WARN_MAYBE_UNINITIALIZED # avoid false positives help This tracer profiles all branch conditions. Every if () taken in the kernel is recorded whether it hit or miss. |