Latest versions of GCC BPF use C23 standard by default. This causes compilation errors in vmlinux.h due to bool types declarations. Add -std=gnu11 to BPF_CFLAGS and CFLAGS. This aligns with the version of the standard used when building the kernel currently [1]. For more details see the discussions at [2] and [3]. [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Makefile#n465 [2] https://lore.kernel.org/bpf/EYcXjcKDCJY7Yb0GGtAAb7nLKPEvrgWdvWpuNzXm2qi6rYMZDixKv5KwfVVMBq17V55xyC-A1wIjrqG3aw-Imqudo9q9X7D7nLU2gWgbN0w=@pm.me/ [3] https://lore.kernel.org/bpf/20250106202715.1232864-1-ihor.solodrai@xxxxx/ CC: Jose E. Marchesi <jose.marchesi@xxxxxxxxxx> Signed-off-by: Ihor Solodrai <ihor.solodrai@xxxxx> --- tools/testing/selftests/bpf/Makefile | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index d5be2f94deef..ea9cee5de0f8 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -41,7 +41,7 @@ srctree := $(patsubst %/,%,$(dir $(srctree))) srctree := $(patsubst %/,%,$(dir $(srctree))) endif -CFLAGS += -g $(OPT_FLAGS) -rdynamic \ +CFLAGS += -g $(OPT_FLAGS) -rdynamic -std=gnu11 \ -Wall -Werror -fno-omit-frame-pointer \ $(GENFLAGS) $(SAN_CFLAGS) $(LIBELF_CFLAGS) \ -I$(CURDIR) -I$(INCLUDE_DIR) -I$(GENDIR) -I$(LIBDIR) \ @@ -447,6 +447,7 @@ CLANG_SYS_INCLUDES = $(call get_sys_includes,$(CLANG),$(CLANG_TARGET_ARCH)) BPF_CFLAGS = -g -Wall -Werror -D__TARGET_ARCH_$(SRCARCH) $(MENDIAN) \ -I$(INCLUDE_DIR) -I$(CURDIR) -I$(APIDIR) \ -I$(abspath $(OUTPUT)/../usr/include) \ + -std=gnu11 \ -fno-strict-aliasing \ -Wno-compare-distinct-pointer-types # TODO: enable me -Wsign-compare @@ -787,9 +788,12 @@ $(OUTPUT)/xdp_features: xdp_features.c $(OUTPUT)/network_helpers.o $(OUTPUT)/xdp $(Q)$(CC) $(CFLAGS) $(filter %.a %.o %.c,$^) $(LDLIBS) -o $@ # Make sure we are able to include and link libbpf against c++. +CXXFLAGS += $(CFLAGS) +CXXFLAGS := $(subst -D_GNU_SOURCE=,,$(CXXFLAGS)) +CXXFLAGS := $(subst -std=gnu11,-std=gnu++11,$(CXXFLAGS)) $(OUTPUT)/test_cpp: test_cpp.cpp $(OUTPUT)/test_core_extern.skel.h $(BPFOBJ) $(call msg,CXX,,$@) - $(Q)$(CXX) $(subst -D_GNU_SOURCE=,,$(CFLAGS)) $(filter %.a %.o %.cpp,$^) $(LDLIBS) -o $@ + $(Q)$(CXX) $(CXXFLAGS) $(filter %.a %.o %.cpp,$^) $(LDLIBS) -o $@ # Benchmark runner $(OUTPUT)/bench_%.o: benchs/bench_%.c bench.h $(BPFOBJ) -- 2.47.1
