On 8/16/2021 5:21 PM, 'Nick Desaulniers' via Clang Built Linux wrote:
As noted in the comment, -mtune= has been supported since GCC 3.4. The
minimum required version of GCC to build the kernel (as specified in
Documentation/process/changes.rst) is GCC 4.9.
tune is not immediately expanded. Instead it defines a macro that will
test via cc-option later values for -mtune=. But we can skip the test
whether to use -mtune= vs. -mcpu=.
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: x86@xxxxxxxxxx
Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Yay for removing stale checks!
Reviewed-by: Nathan Chancellor <nathan@xxxxxxxxxx>
---
arch/x86/Makefile_32.cpu | 6 ------
1 file changed, 6 deletions(-)
diff --git a/arch/x86/Makefile_32.cpu b/arch/x86/Makefile_32.cpu
index cd3056759880..e7355f8b51c2 100644
--- a/arch/x86/Makefile_32.cpu
+++ b/arch/x86/Makefile_32.cpu
@@ -2,13 +2,7 @@
# CPU tuning section - shared with UML.
# Must change only cflags-y (or [yn]), not CFLAGS! That makes a difference for UML.
-#-mtune exists since gcc 3.4
-HAS_MTUNE := $(call cc-option-yn, -mtune=i386)
-ifeq ($(HAS_MTUNE),y)
tune = $(call cc-option,-mtune=$(1),$(2))
-else
-tune = $(call cc-option,-mcpu=$(1),$(2))
-endif
cflags-$(CONFIG_M486SX) += -march=i486
cflags-$(CONFIG_M486) += -march=i486
