diff mbox

kbuild: clang: disable unused variable warnings only when constant

Message ID 1517960811-21674-1-git-send-email-psodagud@codeaurora.org (mailing list archive)
State New, archived
Headers show

Commit Message

Prasad Sodagudi Feb. 6, 2018, 11:46 p.m. UTC 
Currently, GCC disables -Wunused-const-variable, but not
-Wunused-variable, so warns unused variables if they are
non-constant.

While, Clang does not warn unused variables at all regardless of
the const qualifier because -Wno-unused-const-variable is implied
by the stronger option -Wno-unused-variable.

Disable -Wunused-const-variable instead of -Wunused-variable so that
GCC and Clang work in the same way.

Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
---
 Makefile | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Comments

Masahiro Yamada Feb. 7, 2018, 12:22 a.m. UTC | #1 
2018-02-07 8:46 GMT+09:00 Prasad Sodagudi <psodagud@codeaurora.org>:
> Currently, GCC disables -Wunused-const-variable, but not
> -Wunused-variable, so warns unused variables if they are
> non-constant.
>
> While, Clang does not warn unused variables at all regardless of
> the const qualifier because -Wno-unused-const-variable is implied
> by the stronger option -Wno-unused-variable.
>
> Disable -Wunused-const-variable instead of -Wunused-variable so that
> GCC and Clang work in the same way.
>
> Signed-off-by: Prasad Sodagudi <psodagud@codeaurora.org>
> Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>

Applied to linux-kbuild/kbuild.   Thanks!
diff mbox

Patch

diff --git a/Makefile b/Makefile
index 11aff0f..ca0a571 100644
--- a/Makefile
+++ b/Makefile
@@ -700,7 +700,6 @@  KBUILD_CFLAGS += $(stackp-flag)
 
 ifeq ($(cc-name),clang)
 KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,)
-KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable)
 KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier)
 KBUILD_CFLAGS += $(call cc-disable-warning, gnu)
 KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
@@ -718,9 +717,9 @@  else
 # These warnings generated too much noise in a regular build.
 # Use make W=1 to enable them (see scripts/Makefile.extrawarn)
 KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable)
-KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 endif
 
+KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable)
 ifdef CONFIG_FRAME_POINTER
 KBUILD_CFLAGS	+= -fno-omit-frame-pointer -fno-optimize-sibling-calls
 else