selftests/bpf: use simply-expanded variables for libpcap flags

Save pkg-config output for libpcap as simply-expanded variables. For an obscure reason 'shell' call in LDLIBS/CFLAGS recursively expanded variables makes *.test.o files compilation non-parallel when make is executed with -j option. While at it, reuse 'pkg-config --cflags' call to define -DTRAFFIC_MONITOR=1 option, it's exit status is the same as for 'pkg-config --exists'. Fixes: f52403b ("selftests/bpf: Add traffic monitor functions.") Signed-off-by: Eduard Zingerman <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Martin KaFai Lau <[email protected]>
omasanori · Aug 23, 2024 · 5772c34 · 5772c34
1 parent 5cd0aea
commit 5772c34
Showing 1 changed file with 4 additions and 3 deletions.
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
@@ -48,9 +48,10 @@ CFLAGS += -g $(OPT_FLAGS) -rdynamic					\
 LDFLAGS += $(SAN_LDFLAGS)
 LDLIBS += $(LIBELF_LIBS) -lz -lrt -lpthread
 
-LDLIBS += $(shell $(PKG_CONFIG) --libs libpcap 2>/dev/null)
-CFLAGS += $(shell $(PKG_CONFIG) --cflags libpcap 2>/dev/null)
-CFLAGS += $(shell $(PKG_CONFIG) --exists libpcap 2>/dev/null && echo "-DTRAFFIC_MONITOR=1")
+PCAP_CFLAGS	:= $(shell $(PKG_CONFIG) --cflags libpcap 2>/dev/null && echo "-DTRAFFIC_MONITOR=1")
+PCAP_LIBS	:= $(shell $(PKG_CONFIG) --libs libpcap 2>/dev/null)
+LDLIBS += $(PCAP_LIBS)
+CFLAGS += $(PCAP_CFLAGS)
 
 # The following tests perform type punning and they may break strict
 # aliasing rules, which are exploited by both GCC and clang by default