Commit 43174f0d authored by Alan Maguire's avatar Alan Maguire Committed by Andrii Nakryiko
Browse files

libbpf: Silence uninitialized warning/error in btf_dump_dump_type_data 



When compiling libbpf with gcc 4.8.5, we see:

  CC       staticobjs/btf_dump.o
btf_dump.c: In function ‘btf_dump_dump_type_data.isra.24’:
btf_dump.c:2296:5: error: ‘err’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
  if (err < 0)
     ^
cc1: all warnings being treated as errors
make: *** [staticobjs/btf_dump.o] Error 1

While gcc 4.8.5 is too old to build the upstream kernel, it's possible it
could be used to build standalone libbpf which suffers from the same problem.
Silence the error by initializing 'err' to 0.  The warning/error seems to be
a false positive since err is set early in the function.  Regardless we
shouldn't prevent libbpf from building for this.

Fixes: 920d16af ("libbpf: BTF dumper support for typed data")
Signed-off-by: default avatarAlan Maguire <alan.maguire@oracle.com>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1638180040-8037-1-git-send-email-alan.maguire@oracle.com
parent da61e9e3

tools/lib/bpf/btf_dump.c

+1 −1
Original line number Diff line number Diff line
@@ -2216,7 +2216,7 @@ static int btf_dump_dump_type_data(struct btf_dump *d, 
				   __u8 bits_offset,

				   __u8 bit_sz)

{

	int size, err;

	int size, err = 0;



	size = btf_dump_type_data_check_overflow(d, t, id, data, bits_offset);

	if (size < 0)