libbpf: Fix non-C89 loop variable declaration in gen_loader.c

Fix the `int i` declaration inside the for statement. This is non-C89
compliant. See [0] for user report breaking BCC build.

  [0] https://github.com/libbpf/libbpf/issues/403

Fixes: 18f4fccbf314 ("libbpf: Update gen_loader to emit BTF_KIND_FUNC relocations")
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/bpf/20211105191055.3324874-1-andrii@kernel.org

diff --git a/tools/lib/bpf/gen_loader.c b/tools/lib/bpf/gen_loader.c
index 502dea5..2e10776 100644 (file)
--- a/tools/lib/bpf/gen_loader.c
+++ b/tools/lib/bpf/gen_loader.c
@@ -584,8 +584,9 @@ void bpf_gen__record_extern(struct bpf_gen *gen, const char *name, bool is_weak,
 static struct ksym_desc *get_ksym_desc(struct bpf_gen *gen, struct ksym_relo_desc *relo)
 {
        struct ksym_desc *kdesc;
+       int i;
 
-       for (int i = 0; i < gen->nr_ksyms; i++) {
+       for (i = 0; i < gen->nr_ksyms; i++) {
                if (!strcmp(gen->ksyms[i].name, relo->name)) {
                        gen->ksyms[i].ref++;
                        return &gen->ksyms[i];