| Message ID | 908498f794661c44dca54da9e09dc0c382df6fcb.1580425879.git.hex@fb.com |
|---|---|
| State | Accepted |
| Delegated to: | BPF Maintainers |
| Headers | show |
| Series | [v3,bpf] runqslower: fix Makefile | expand |
On Thu, Jan 30, 2020 at 3:14 PM Yulia Kartseva <hex@fb.com> wrote: > > 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@fb.com> > Acked-by: Andrii Nakryiko <andriin@fb.com> Applied. Thanks
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
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@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> --- tools/bpf/runqslower/Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)