BACKPORT: kbuild: Add __cc-option macro

cc-option uses KBUILD_CFLAGS and KBUILD_CPPFLAGS when it determines
whether an option is supported or not. This is fine for options used to
build the kernel itself, however some components like the x86 boot code
use a different set of flags.

Add the new macro __cc-option which is a more generic version of
cc-option with additional parameters. One parameter is the compiler
with which the check should be performed, the other the compiler options
to be used instead KBUILD_C*FLAGS.

Refactor cc-option and hostcc-option to use __cc-option and move
hostcc-option to scripts/Kbuild.include.

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
(cherry picked from commit 9f3f1fd299768782465cb32cdf0dd4528d11f26b)
Signed-off-by: Greg Hackmann <ghackmann@google.com>

Conflicts:
	scripts/Kbuild.include

Change-Id: I4c8288b9c74bd6b9199307a0e04b78a27e28361d
This commit is contained in:
Matthias Kaehlcke 2017-06-21 16:28:03 -07:00 committed by Greg Hackmann
parent 3afdf761c5
commit 423ba0fede
2 changed files with 17 additions and 3 deletions

View file

@ -301,7 +301,7 @@ CONFIG_SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
HOSTCC = gcc
HOSTCXX = g++
HOSTCFLAGS = -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89
HOSTCFLAGS := -Wall -Wmissing-prototypes -Wstrict-prototypes -O2 -fomit-frame-pointer -std=gnu89
HOSTCXXFLAGS = -O2
ifeq ($(shell $(HOSTCC) -v 2>&1 | grep -c "clang version"), 1)

View file

@ -107,11 +107,25 @@ as-option = $(call try-run,\
as-instr = $(call try-run,\
printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
# __cc-option
# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
__cc-option = $(call try-run,\
$(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
# Do not attempt to build with gcc plugins during cc-option tests.
# (And this uses delayed resolution so the flags will be up to date.)
CC_OPTION_CFLAGS = $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS))
# cc-option
# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
cc-option = $(call try-run,\
$(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",$(1),$(2))
cc-option = $(call __cc-option, $(CC),\
$(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2))
# hostcc-option
# Usage: cflags-y += $(call hostcc-option,-march=winchip-c6,-march=i586)
hostcc-option = $(call __cc-option, $(HOSTCC),\
$(HOSTCFLAGS) $(HOST_EXTRACFLAGS),$(1),$(2))
# cc-option-yn
# Usage: flag := $(call cc-option-yn,-march=winchip-c6)