[PATCH] kbuild: deprecate cc-option-align

From: Masahiro Yamada
Date: Mon Jun 19 2017 - 03:31:05 EST


Documentation/kbuild/makefiles.txt says the change for align options
occurred at GCC 3.0, and Documentation/process/changes.rst says the
minimal supported GCC version is 3.2, so it should be safe to hard-code
-falign* options.

Fix the only user arch/x86/Makefile_32.cpu and deprecate the
cc-option-align.

Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---

x86 maintainers,

If this patch looks OK, could you give me Acked-by?


Documentation/kbuild/makefiles.txt | 16 ----------------
arch/x86/Makefile_32.cpu | 7 +++----
scripts/Kbuild.include | 5 -----
3 files changed, 3 insertions(+), 25 deletions(-)

diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt
index 1c49e87cea4f..247fb331c4b2 100644
--- a/Documentation/kbuild/makefiles.txt
+++ b/Documentation/kbuild/makefiles.txt
@@ -486,22 +486,6 @@ more details, with real examples.
respectively.
Note: cc-option-yn uses KBUILD_CFLAGS for $(CC) options

- cc-option-align
- gcc versions >= 3.0 changed the type of options used to specify
- alignment of functions, loops etc. $(cc-option-align), when used
- as prefix to the align options, will select the right prefix:
- gcc < 3.00
- cc-option-align = -malign
- gcc >= 3.00
- cc-option-align = -falign
-
- Example:
- KBUILD_CFLAGS += $(cc-option-align)-functions=4
-
- In the above example, the option -falign-functions=4 is used for
- gcc >= 3.00. For gcc < 3.00, -malign-functions=4 is used.
- Note: cc-option-align uses KBUILD_CFLAGS for $(CC) options
-
cc-disable-warning
cc-disable-warning checks if gcc supports a given warning and returns
the commandline switch to disable it. This special function is needed,
diff --git a/arch/x86/Makefile_32.cpu b/arch/x86/Makefile_32.cpu
index a45eb15b7cf2..f3717d36718a 100644
--- a/arch/x86/Makefile_32.cpu
+++ b/arch/x86/Makefile_32.cpu
@@ -9,7 +9,6 @@ else
tune = $(call cc-option,-mcpu=$(1),$(2))
endif

-align := $(cc-option-align)
cflags-$(CONFIG_M486) += -march=i486
cflags-$(CONFIG_M586) += -march=i586
cflags-$(CONFIG_M586TSC) += -march=i586
@@ -24,11 +23,11 @@ cflags-$(CONFIG_MK6) += -march=k6
# They make zero difference whatsosever to performance at this time.
cflags-$(CONFIG_MK7) += -march=athlon
cflags-$(CONFIG_MK8) += $(call cc-option,-march=k8,-march=athlon)
-cflags-$(CONFIG_MCRUSOE) += -march=i686 $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
-cflags-$(CONFIG_MEFFICEON) += -march=i686 $(call tune,pentium3) $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
+cflags-$(CONFIG_MCRUSOE) += -march=i686 -falign-functions=0 -falign-jumps=0 -falign-loops=0
+cflags-$(CONFIG_MEFFICEON) += -march=i686 $(call tune,pentium3) -falign-functions=0 -falign-jumps=0 -falign-loops=0
cflags-$(CONFIG_MWINCHIPC6) += $(call cc-option,-march=winchip-c6,-march=i586)
cflags-$(CONFIG_MWINCHIP3D) += $(call cc-option,-march=winchip2,-march=i586)
-cflags-$(CONFIG_MCYRIXIII) += $(call cc-option,-march=c3,-march=i486) $(align)-functions=0 $(align)-jumps=0 $(align)-loops=0
+cflags-$(CONFIG_MCYRIXIII) += $(call cc-option,-march=c3,-march=i486) -falign-functions=0 -falign-jumps=0 -falign-loops=0
cflags-$(CONFIG_MVIAC3_2) += $(call cc-option,-march=c3-2,-march=i686)
cflags-$(CONFIG_MVIAC7) += -march=i686
cflags-$(CONFIG_MCORE2) += -march=i686 $(call tune,core2)
diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include
index 5001bf9b6579..9a7697d17fb5 100644
--- a/scripts/Kbuild.include
+++ b/scripts/Kbuild.include
@@ -133,11 +133,6 @@ hostcc-option = $(call __cc-option, $(HOSTCC),\
cc-option-yn = $(call try-run,\
$(CC) -Werror $(KBUILD_CPPFLAGS) $(CC_OPTION_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)

-# cc-option-align
-# Prefix align with either -falign or -malign
-cc-option-align = $(subst -functions=0,,\
- $(call cc-option,-falign-functions=0,-malign-functions=0))
-
# cc-disable-warning
# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
cc-disable-warning = $(call try-run,\
--
2.7.4