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| author | Tom Hughes <tomhughes@chromium.org> | 2021-09-28 00:12:34 +0000 |
|---|---|---|
| committer | Commit Bot <commit-bot@chromium.org> | 2021-11-03 22:59:52 +0000 |
| commit | d6271635b6a8cdc875626433cef4faed4d068fcc (patch) | |
| tree | 8a36472490525ce3b92a9bbc02f3e1a1f6294482 | |
| parent | 37493c0d4726d658902f41dbd521f30323b025ba (diff) | |
| download | chrome-ec-d6271635b6a8cdc875626433cef4faed4d068fcc.tar.gz | |
core/cortex-m0: Use builtins from compiler-rt when using clang
When compiling with clang, use the builtins from compiler-rt rather than
our own hand-rolled versions. When trying to compile with our versions,
clang fails to link:
ld.lld: error: core/cortex-m0/div.S:52:(.text.__aeabi_idiv+0x10):
unrecognized relocation R_ARM_THM_JUMP8
ld.lld: error: core/cortex-m0/div.S:97:(.text.__aeabi_idivmod+0x24):
unrecognized relocation R_ARM_THM_JUMP8
BRANCH=none
BUG=b:172020503
TEST=CC=clang make BOARD=servo_v4
TEST=./util/compare_build.sh -b all -j 120
=> MATCH
Signed-off-by: Tom Hughes <tomhughes@chromium.org>
Change-Id: I33db397c13bcdcb63bd931d0d8425f9f02a76327
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3188640
Reviewed-by: Abe Levkoy <alevkoy@chromium.org>
| -rw-r--r-- | core/cortex-m0/build.mk | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/core/cortex-m0/build.mk b/core/cortex-m0/build.mk index 40764f53c6..8d2002bad5 100644 --- a/core/cortex-m0/build.mk +++ b/core/cortex-m0/build.mk @@ -15,6 +15,8 @@ $(call set-option,CROSS_COMPILE,\ CFLAGS_CPU+=-mthumb ifeq ($(cc-name),clang) CFLAGS_CPU+=-Oz # Like -Os (and thus -O2), but reduces code size further. +# Link compiler-rt when using clang, so clang finds the builtins it provides. +LDFLAGS_EXTRA+=-lclang_rt.builtins-arm else CFLAGS_CPU+=-Os CFLAGS_CPU+=-mno-sched-prolog @@ -26,8 +28,17 @@ CFLAGS_CPU+=-flto LDFLAGS_EXTRA+=-flto endif -core-y=cpu.o debug.o init.o thumb_case.o div.o lmul.o ldivmod.o mula.o uldivmod.o -core-y+=vecttable.o __builtin.o +core-y=cpu.o debug.o init.o thumb_case.o mula.o +# When using clang, we get these as builtins from compiler-rt. +ifneq ($(cc-name),clang) +core-y+=div.o lmul.o ldivmod.o uldivmod.o +endif + +core-y+=vecttable.o +# When using clang, we get these as builtins from compiler-rt. +ifneq ($(cc-name),clang) +core-y+=__builtin.o +endif core-$(CONFIG_COMMON_PANIC_OUTPUT)+=panic.o core-$(CONFIG_COMMON_RUNTIME)+=switch.o task.o |