[PATCH v2 4/5] powerpc/kbuild: Use flags variables rather than overriding LD/CC/AS

Nicholas Piggin
2018-05-10T05:17:23Z

The powerpc toolchain can compile combinations of 32/64 bit and
big/little endian, so it's convenient to consider, e.g.,

`CC -m64 -mbig-endian`

To be the C compiler for the purpose of invoking it to build target
artifacts. So overriding the the CC variable to include thse flags
works for this purpose.

Unfortunately that is not compatible with the way the proposed new
Kconfig macro language will work.

After previous patches in this series, these flags can be carefully
passed in using flags instead.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
arch/powerpc/Makefile | 16 +++++++++-------
scripts/recordmcount.pl | 8 ++++++++
2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/Makefile b/arch/powerpc/Makefile
index a40f59ca2afe..5f3ec8029e50 100644
--- a/arch/powerpc/Makefile
+++ b/arch/powerpc/Makefile
@@ -70,13 +70,15 @@ endif
endif

ifeq ($(CONFIG_CPU_LITTLE_ENDIAN),y)
-override LD += -EL
+KBUILD_CFLAGS += -mlittle-endian
+LDFLAGS += -EL
LDEMULATION := lppc
GNUTARGET := powerpcle
MULTIPLEWORD := -mno-multiple
KBUILD_CFLAGS_MODULE += $(call cc-option,-mno-save-toc-indirect)
else
-override LD += -EB
+KBUILD_CFLAGS += $(call cc-option,-mbig-endian)
+LDFLAGS += -EB
LDEMULATION := ppc
GNUTARGET := powerpc
MULTIPLEWORD := -mmultiple
@@ -89,19 +91,19 @@ aflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mabi=elfv1)
aflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mabi=elfv2
endif

-cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian
-cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian)
ifneq ($(cc-name),clang)
cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mno-strict-align
endif

+cflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian)
+cflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian
aflags-$(CONFIG_CPU_BIG_ENDIAN) += $(call cc-option,-mbig-endian)
aflags-$(CONFIG_CPU_LITTLE_ENDIAN) += -mlittle-endian

ifeq ($(HAS_BIARCH),y)
-override AS += -a$(BITS)
-override LD += -m elf$(BITS)$(LDEMULATION)
-override CC += -m$(BITS)
+KBUILD_CFLAGS += -m$(BITS)
+KBUILD_AFLAGS += -m$(BITS) -Wl,-a$(BITS)
+LDFLAGS += -m elf$(BITS)$(LDEMULATION)
KBUILD_ARFLAGS += --target=elf$(BITS)-$(GNUTARGET)
endif

diff --git a/scripts/recordmcount.pl b/scripts/recordmcount.pl
index 191eb949d52c..919711dd9d6c 100755
--- a/scripts/recordmcount.pl
+++ b/scripts/recordmcount.pl
@@ -274,6 +274,14 @@ if ($arch eq "x86_64") {
if ($bits == 64) {
$type = ".quad";
}
+ $ld .= " -EB ";
+ if ($endian eq "big") {
+ $cc .= " -mbig-endian ";
+ $ld .= " -EB ";
+ } else {
+ $cc .= " -mlittle-endian ";
+ $ld .= " -EL ";
+ }

} elsif ($arch eq "arm") {
$alignment = 2;
--
2.17.0