When compiling an eBPF prog fails, make still returns 0, because failing clang command's output is piped to llc and therefore its exit status is ignored. When clang fails, pipe the string "clang failed" to llc. This will make llc fail with an informative error message. This solution was chosen over using pipefail, having separate targets or getting rid of llc invocation due to its simplicity. In addition, pull Kbuild.include in order to get .DELETE_ON_ERROR target, which would cause partial .o files to be removed. Signed-off-by: Ilya Leoshkevich <iii@xxxxxxxxxxxxx> --- v1->v2: use intermediate targets instead of pipefail v2->v3: pipe "clang failed" instead of using intermediate targets tools/testing/selftests/bpf/Makefile | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index e36356e2377e..e375f399b7a6 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 +include ../../../../scripts/Kbuild.include LIBDIR := ../../../lib BPFDIR := $(LIBDIR)/bpf @@ -185,8 +186,8 @@ $(ALU32_BUILD_DIR)/test_progs_32: prog_tests/*.c $(ALU32_BUILD_DIR)/%.o: progs/%.c $(ALU32_BUILD_DIR) \ $(ALU32_BUILD_DIR)/test_progs_32 - $(CLANG) $(CLANG_FLAGS) \ - -O2 -target bpf -emit-llvm -c $< -o - | \ + ($(CLANG) $(CLANG_FLAGS) -O2 -target bpf -emit-llvm -c $< -o - || \ + echo "clang failed") | \ $(LLC) -march=bpf -mattr=+alu32 -mcpu=$(CPU) $(LLC_FLAGS) \ -filetype=obj -o $@ ifeq ($(DWARF2BTF),y) @@ -197,16 +198,16 @@ endif # Have one program compiled without "-target bpf" to test whether libbpf loads # it successfully $(OUTPUT)/test_xdp.o: progs/test_xdp.c - $(CLANG) $(CLANG_FLAGS) \ - -O2 -emit-llvm -c $< -o - | \ + ($(CLANG) $(CLANG_FLAGS) -O2 -emit-llvm -c $< -o - || \ + echo "clang failed") | \ $(LLC) -march=bpf -mcpu=$(CPU) $(LLC_FLAGS) -filetype=obj -o $@ ifeq ($(DWARF2BTF),y) $(BTF_PAHOLE) -J $@ endif $(OUTPUT)/%.o: progs/%.c - $(CLANG) $(CLANG_FLAGS) \ - -O2 -target bpf -emit-llvm -c $< -o - | \ + ($(CLANG) $(CLANG_FLAGS) -O2 -target bpf -emit-llvm -c $< -o - || \ + echo "clang failed") | \ $(LLC) -march=bpf -mcpu=$(CPU) $(LLC_FLAGS) -filetype=obj -o $@ ifeq ($(DWARF2BTF),y) $(BTF_PAHOLE) -J $@ -- 2.21.0