Fix undefined reference linker errors when building runqslower with
gcc 7.4.0 on Ubuntu 18.04.
The issue is with misplaced -lelf, -lz options in Makefile:
$(Q)$(CC) $(CFLAGS) -lelf -lz $^ -o $@
-lelf, -lz options should follow the list of target dependencies:
$(Q)$(CC) $(CFLAGS) $^ -lelf -lz -o $@
or after substitution
cc -g -Wall runqslower.o libbpf.a -lelf -lz -o runqslower
The current order of gcc params causes failure in libelf symbols resolution,
e.g. undefined reference to `elf_memory'
Fixes: 9c01546d26d2 ("tools/bpf: Add runqslower tool to tools/bpf")
Signed-off-by: Julia Kartseva <hex@xxxxxx>
Acked-by: Andrii Nakryiko <andriin@xxxxxx>
---
tools/bpf/runqslower/Makefile | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/bpf/runqslower/Makefile b/tools/bpf/runqslower/Makefile
index 0c021352b..87eae5be9 100644
--- a/tools/bpf/runqslower/Makefile
+++ b/tools/bpf/runqslower/Makefile
@@ -41,7 +41,7 @@ clean:
$(OUTPUT)/runqslower: $(OUTPUT)/runqslower.o $(BPFOBJ)
$(call msg,BINARY,$@)
- $(Q)$(CC) $(CFLAGS) -lelf -lz $^ -o $@
+ $(Q)$(CC) $(CFLAGS) $^ -lelf -lz -o $@
$(OUTPUT)/runqslower.o: runqslower.h $(OUTPUT)/runqslower.skel.h \
$(OUTPUT)/runqslower.bpf.o
--
2.17.1
