From 870f09f1ba3014e2c157b14299c172b4bb716638 Mon Sep 17 00:00:00 2001 From: Viktor Malik Date: Wed, 25 Oct 2023 08:19:12 +0200 Subject: samples/bpf: Allow building with custom CFLAGS/LDFLAGS Currently, it is not possible to specify custom flags when building samples/bpf. The flags are defined in TPROGS_CFLAGS/TPROGS_LDFLAGS variables, however, when trying to override those from the make command, compilation fails. For example, when trying to build with PIE: $ make -C samples/bpf TPROGS_CFLAGS="-fpie" TPROGS_LDFLAGS="-pie" This is because samples/bpf/Makefile updates these variables, especially appends include paths to TPROGS_CFLAGS and these updates are overridden by setting the variables from the make command. This patch introduces variables TPROGS_USER_CFLAGS/TPROGS_USER_LDFLAGS for this purpose, which can be set from the make command and their values are propagated to TPROGS_CFLAGS/TPROGS_LDFLAGS. Signed-off-by: Viktor Malik Signed-off-by: Daniel Borkmann Link: https://lore.kernel.org/bpf/2d81100b830a71f0e72329cc7781edaefab75f62.1698213811.git.vmalik@redhat.com --- samples/bpf/Makefile | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'samples') diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 90af76fa9dd8..5a9805edec93 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -150,6 +150,9 @@ always-y += ibumad_kern.o always-y += hbm_out_kern.o always-y += hbm_edt_kern.o +TPROGS_CFLAGS = $(TPROGS_USER_CFLAGS) +TPROGS_LDFLAGS = $(TPROGS_USER_LDFLAGS) + ifeq ($(ARCH), arm) # Strip all except -D__LINUX_ARM_ARCH__ option needed to handle linux # headers when arm instruction set identification is requested. @@ -316,7 +319,7 @@ XDP_SAMPLE_CFLAGS += -Wall -O2 \ -I$(LIBBPF_INCLUDE) \ -I$(src)/../../tools/testing/selftests/bpf -$(obj)/$(XDP_SAMPLE): TPROGS_CFLAGS = $(XDP_SAMPLE_CFLAGS) +$(obj)/$(XDP_SAMPLE): TPROGS_CFLAGS = $(XDP_SAMPLE_CFLAGS) $(TPROGS_USER_CFLAGS) $(obj)/$(XDP_SAMPLE): $(src)/xdp_sample_user.h $(src)/xdp_sample_shared.h # Override includes for trace_helpers.o because __must_check won't be defined # in our include path. -- cgit v1.2.3-70-g09d2