| Message ID | 20220614121045.1046475-1-broonie@kernel.org (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | selftests: Fix clang cross compilation | expand |
On 6/14/22 6:10 AM, Mark Brown wrote: > Unlike GCC clang uses a single compiler image to support multiple target > architectures meaning that we can't simply rely on CROSS_COMPILE to select > the output architecture. Instead we must pass --target to the compiler to > tell it what to output, kselftest was not doing this so cross compilation > of kselftest using clang resulted in kselftest being built for the host > architecture. > > More work is required to fix tests using custom rules but this gets the > bulk of things building. > > Signed-off-by: Mark Brown <broonie@kernel.org> > --- > tools/testing/selftests/lib.mk | 25 +++++++++++++++++++++++-- > 1 file changed, 23 insertions(+), 2 deletions(-) > Thank you. I will apply this for the next rc. thanks, -- Shuah
diff --git a/tools/testing/selftests/lib.mk b/tools/testing/selftests/lib.mk index 2a2d240cdc1b..1a5cc3cd97ec 100644 --- a/tools/testing/selftests/lib.mk +++ b/tools/testing/selftests/lib.mk @@ -7,10 +7,31 @@ else ifneq ($(filter -%,$(LLVM)),) LLVM_SUFFIX := $(LLVM) endif -CC := $(LLVM_PREFIX)clang$(LLVM_SUFFIX) +CLANG_TARGET_FLAGS_arm := arm-linux-gnueabi +CLANG_TARGET_FLAGS_arm64 := aarch64-linux-gnu +CLANG_TARGET_FLAGS_hexagon := hexagon-linux-musl +CLANG_TARGET_FLAGS_m68k := m68k-linux-gnu +CLANG_TARGET_FLAGS_mips := mipsel-linux-gnu +CLANG_TARGET_FLAGS_powerpc := powerpc64le-linux-gnu +CLANG_TARGET_FLAGS_riscv := riscv64-linux-gnu +CLANG_TARGET_FLAGS_s390 := s390x-linux-gnu +CLANG_TARGET_FLAGS_x86 := x86_64-linux-gnu +CLANG_TARGET_FLAGS := $(CLANG_TARGET_FLAGS_$(ARCH)) + +ifeq ($(CROSS_COMPILE),) +ifeq ($(CLANG_TARGET_FLAGS),) +$(error Specify CROSS_COMPILE or add '--target=' option to lib.mk +else +CLANG_FLAGS += --target=$(CLANG_TARGET_FLAGS) +endif # CLANG_TARGET_FLAGS +else +CLANG_FLAGS += --target=$(notdir $(CROSS_COMPILE:%-=%)) +endif # CROSS_COMPILE + +CC := $(LLVM_PREFIX)clang$(LLVM_SUFFIX) $(CLANG_FLAGS) -fintegrated-as else CC := $(CROSS_COMPILE)gcc -endif +endif # LLVM ifeq (0,$(MAKELEVEL)) ifeq ($(OUTPUT),)
Unlike GCC clang uses a single compiler image to support multiple target architectures meaning that we can't simply rely on CROSS_COMPILE to select the output architecture. Instead we must pass --target to the compiler to tell it what to output, kselftest was not doing this so cross compilation of kselftest using clang resulted in kselftest being built for the host architecture. More work is required to fix tests using custom rules but this gets the bulk of things building. Signed-off-by: Mark Brown <broonie@kernel.org> --- tools/testing/selftests/lib.mk | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-)