github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-07-28 18:21:24 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

bpftool: Pass host flags to bootstrap libbpf

Browse Source 
bpftool builds a bootstrap libbpf with HOSTCC, but the libbpf submake can
still inherit target build flags through CFLAGS. This can break cross
builds when host objects are compiled with target-only options.

Since HOST_CFLAGS contains warning options that are not suitable for
building libbpf, use LIBBPF_BOOTSTRAP_CFLAGS with the warning options
removed to build the bootstrap libbpf. Clear EXTRA_CFLAGS so target
extra flags are not mixed into the host bootstrap libbpf build.

Signed-off-by: Leo Yan <leo.yan@arm.com>
Acked-by: Quentin Monnet <qmo@kernel.org>
Link: https://lore.kernel.org/r/20260602-tools_build_fix_zero_init_bpf_only-v2-1-c76e5250ea1c@arm.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This commit is contained in:
Leo Yan 2026-06-02 15:47:10 +01:00 committed by Alexei Starovoitov
parent 1f24de6b2c
commit 9080b97689
1 changed files with 5 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
tools/bpf/bpftool/Makefile
View File

@ -47,7 +47,8 @@ $(LIBBPF_INTERNAL_HDRS): $(LIBBPF_HDRS_DIR)/%.h: $(BPF_DIR)/%.h | $(LIBBPF_HDRS_
$(LIBBPF_BOOTSTRAP): $(wildcard $(BPF_DIR)/*.[ch] $(BPF_DIR)/Makefile) | $(LIBBPF_BOOTSTRAP_OUTPUT)
$(Q)$(MAKE) -C $(BPF_DIR) OUTPUT=$(LIBBPF_BOOTSTRAP_OUTPUT) \
DESTDIR=$(LIBBPF_BOOTSTRAP_DESTDIR:/=) prefix= \
ARCH= CROSS_COMPILE= CC="$(HOSTCC)" LD="$(HOSTLD)" AR="$(HOSTAR)" $@ install_headers
ARCH= CROSS_COMPILE= CC="$(HOSTCC)" LD="$(HOSTLD)" AR="$(HOSTAR)" \
CFLAGS="$(LIBBPF_BOOTSTRAP_CFLAGS)" EXTRA_CFLAGS= $@ install_headers
$(LIBBPF_BOOTSTRAP_INTERNAL_HDRS): $(LIBBPF_BOOTSTRAP_HDRS_DIR)/%.h: $(BPF_DIR)/%.h | $(LIBBPF_BOOTSTRAP_HDRS_DIR)
$(call QUIET_INSTALL, $@)
@ -92,6 +93,9 @@ HOST_CFLAGS := $(subst -I$(LIBBPF_INCLUDE),-I$(LIBBPF_BOOTSTRAP_INCLUDE),\
$(subst $(CLANG_CROSS_FLAGS),,$(CFLAGS)))
HOST_LDFLAGS := $(LDFLAGS)
# Remove warnings for libbpf bootstrap build
LIBBPF_BOOTSTRAP_CFLAGS := $(filter-out -W -Wall -Wextra -Wformat -Wformat-signedness,$(HOST_CFLAGS))
INSTALL ?= install
RM ?= rm -f