Merge tag 'Wstringop-overflow-for-6.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux

610347ef · Linus Torvalds <[email protected]> · 2024-01-22 09:47:24 -08:00

Pull stringop-overflow warning update from Gustavo A. R. Silva:
 "Enable -Wstringop-overflow globally.

  I waited for the release of -rc1 to run a final build-test on top of
  it before sending this pull request. Fortunatelly, after building 358
  kernels overnight (basically all supported archs with a wide variety
  of configs), no more warnings have surfaced! :)

  Thus, we are in a good position to enable this compiler option for all
  versions of GCC that support it, with the exception of GCC-11, which
  appears to have some issues with this option [1]"

Link: https://lore.kernel.org/lkml/[email protected]/ [1]

* tag 'Wstringop-overflow-for-6.8-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux:
  init: Kconfig: Disable -Wstringop-overflow for GCC-11
  Makefile: Enable -Wstringop-overflow globally

Commit: 610347effc2ecb5ededf5037e82240b151f883ab
Parents: 0f0d819a · a5e0ace0

Merge commit. Changes below are compared with the first parent: 0f0d819a.

Changes

3 files changed · +16 −2

File	Status	Add	Del	Content
Makefile	modified	+4	−0	View file
init/Kconfig	modified	+12	−0	View file
scripts/Makefile.extrawarn	modified	+0	−2	View file

Makefile

View file

diff --git a/Makefile b/Makefile
index 9869f57..9f9b76d 100644
--- a/Makefile
+++ b/Makefile
@@ -986,6 +986,10 @@ NOSTDINC_FLAGS += -nostdinc
 # perform bounds checking.
 KBUILD_CFLAGS += $(call cc-option, -fstrict-flex-arrays=3)
 
+#Currently, disable -Wstringop-overflow for GCC 11, globally.
+KBUILD_CFLAGS-$(CONFIG_CC_NO_STRINGOP_OVERFLOW) += $(call cc-option, -Wno-stringop-overflow)
+KBUILD_CFLAGS-$(CONFIG_CC_STRINGOP_OVERFLOW) += $(call cc-option, -Wstringop-overflow)
+
 # disable invalid "can't wrap" optimizations for signed / pointers
 KBUILD_CFLAGS	+= -fno-strict-overflow
 

init/Kconfig

View file

diff --git a/init/Kconfig b/init/Kconfig
index 8df18f3..8d4e836 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -876,6 +876,18 @@ config CC_NO_ARRAY_BOUNDS
 	bool
 	default y if CC_IS_GCC && GCC_VERSION >= 110000 && GCC11_NO_ARRAY_BOUNDS
 
+# Currently, disable -Wstringop-overflow for GCC 11, globally.
+config GCC11_NO_STRINGOP_OVERFLOW
+	def_bool y
+
+config CC_NO_STRINGOP_OVERFLOW
+	bool
+	default y if CC_IS_GCC && GCC_VERSION >= 110000 && GCC_VERSION < 120000 && GCC11_NO_STRINGOP_OVERFLOW
+
+config CC_STRINGOP_OVERFLOW
+	bool
+	default y if CC_IS_GCC && !CC_NO_STRINGOP_OVERFLOW
+
 #
 # For architectures that know their GCC __int128 support is sound
 #

scripts/Makefile.extrawarn

View file

diff --git a/scripts/Makefile.extrawarn b/scripts/Makefile.extrawarn
index 9b7a37a..a9e552a 100644
--- a/scripts/Makefile.extrawarn
+++ b/scripts/Makefile.extrawarn
@@ -97,7 +97,6 @@ KBUILD_CFLAGS += $(call cc-option, -Wunused-const-variable)
 KBUILD_CFLAGS += $(call cc-option, -Wpacked-not-aligned)
 KBUILD_CFLAGS += $(call cc-option, -Wformat-overflow)
 KBUILD_CFLAGS += $(call cc-option, -Wformat-truncation)
-KBUILD_CFLAGS += $(call cc-option, -Wstringop-overflow)
 KBUILD_CFLAGS += $(call cc-option, -Wstringop-truncation)
 
 KBUILD_CPPFLAGS += -Wundef
@@ -113,7 +112,6 @@ KBUILD_CFLAGS += $(call cc-disable-warning, restrict)
 KBUILD_CFLAGS += $(call cc-disable-warning, packed-not-aligned)
 KBUILD_CFLAGS += $(call cc-disable-warning, format-overflow)
 KBUILD_CFLAGS += $(call cc-disable-warning, format-truncation)
-KBUILD_CFLAGS += $(call cc-disable-warning, stringop-overflow)
 KBUILD_CFLAGS += $(call cc-disable-warning, stringop-truncation)
 
 ifdef CONFIG_CC_IS_CLANG