From: Alexander Lobakin alexandr.lobakin@intel.com
[ Upstream commit e64fbcaa7a666f16329b1c67af15ea501bc84586 ]
Clang (13) doesn't get the jokes about specifying libraries to link in cclags of individual .o objects:
clang-13: warning: -lm: 'linker' input unused [-Wunused-command-line-argument] [ ... ] LD samples/bpf/xdp_redirect_cpu LD samples/bpf/xdp_redirect_map_multi LD samples/bpf/xdp_redirect_map LD samples/bpf/xdp_redirect LD samples/bpf/xdp_monitor /usr/bin/ld: samples/bpf/xdp_sample_user.o: in function `sample_summary_print': xdp_sample_user.c:(.text+0x84c): undefined reference to `floor' /usr/bin/ld: xdp_sample_user.c:(.text+0x870): undefined reference to `ceil' /usr/bin/ld: xdp_sample_user.c:(.text+0x8cf): undefined reference to `floor' /usr/bin/ld: xdp_sample_user.c:(.text+0x8f3): undefined reference to `ceil' [ more ]
Specify '-lm' as ldflags for all xdp_sample_user.o users in the main Makefile and remove it from ccflags of ^ in Makefile.target -- just like it's done for all other samples. This works with all compilers.
Fixes: 6e1051a54e31 ("samples: bpf: Convert xdp_monitor to XDP samples helper") Fixes: b926c55d856c ("samples: bpf: Convert xdp_redirect to XDP samples helper") Fixes: e531a220cc59 ("samples: bpf: Convert xdp_redirect_cpu to XDP samples helper") Fixes: bbe65865aa05 ("samples: bpf: Convert xdp_redirect_map to XDP samples helper") Fixes: 594a116b2aa1 ("samples: bpf: Convert xdp_redirect_map_multi to XDP samples helper") Signed-off-by: Alexander Lobakin alexandr.lobakin@intel.com Signed-off-by: Andrii Nakryiko andrii@kernel.org Acked-by: Kumar Kartikeya Dwivedi memxor@gmail.com Link: https://lore.kernel.org/bpf/20211203195004.5803-2-alexandr.lobakin@intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- samples/bpf/Makefile | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile index 8ac8573946e1a..c6e38e43c3fd0 100644 --- a/samples/bpf/Makefile +++ b/samples/bpf/Makefile @@ -213,6 +213,11 @@ TPROGS_LDFLAGS := -L$(SYSROOT)/usr/lib endif
TPROGS_LDLIBS += $(LIBBPF) -lelf -lz +TPROGLDLIBS_xdp_monitor += -lm +TPROGLDLIBS_xdp_redirect += -lm +TPROGLDLIBS_xdp_redirect_cpu += -lm +TPROGLDLIBS_xdp_redirect_map += -lm +TPROGLDLIBS_xdp_redirect_map_multi += -lm TPROGLDLIBS_tracex4 += -lrt TPROGLDLIBS_trace_output += -lrt TPROGLDLIBS_map_perf_test += -lrt @@ -342,7 +347,7 @@ $(obj)/hbm_edt_kern.o: $(src)/hbm.h $(src)/hbm_kern.h
# Override includes for xdp_sample_user.o because $(srctree)/usr/include in # TPROGS_CFLAGS causes conflicts -XDP_SAMPLE_CFLAGS += -Wall -O2 -lm \ +XDP_SAMPLE_CFLAGS += -Wall -O2 \ -I$(src)/../../tools/include \ -I$(src)/../../tools/include/uapi \ -I$(LIBBPF_INCLUDE) \