bpftool: Fix -Wuninitialized-const-pointer warnings with clang >= 21 v2

This fixes the build with -Werror -Wall.

btf_dumper.c:71:31: error: variable 'finfo' is uninitialized when passed as a const pointer argument here [-Werror,-Wuninitialized-const-pointer]
   71 |         info.func_info = ptr_to_u64(&finfo);
      |                                      ^~~~~

prog.c:2294:31: error: variable 'func_info' is uninitialized when passed as a const pointer argument here [-Werror,-Wuninitialized-const-pointer]
 2294 |         info.func_info = ptr_to_u64(&func_info);
      |

v2:
  - Initialize instead of using memset.

Signed-off-by: Tom Stellard <[email protected]>
Acked-by: Quentin Monnet <[email protected]>

Author: tstellar

tools/bpf/bpftool/btf_dumper.c

@@ -38,7 +38,9 @@ static int dump_prog_id_as_func_ptr(const struct btf_dumper *d,
 	__u32 info_len = sizeof(info);
 	const char *prog_name = NULL;
 	struct btf *prog_btf = NULL;
-	struct bpf_func_info finfo;
+	/* Initialize finfo to silence -Wuninitialized-const-pointer warning
+	 * in clang >= 21. */
+	struct bpf_func_info finfo = {};
 	__u32 finfo_rec_size;
 	char prog_str[1024];
 	int err;

tools/bpf/bpftool/prog.c

@@ -2262,7 +2262,9 @@ static void profile_print_readings(void)
 
 static char *profile_target_name(int tgt_fd)
 {
-	struct bpf_func_info func_info;
+	/* Initialize func_info to silence -Wuninitialized-const-pointer
+	 * warning in clang >= 21. */
+	struct bpf_func_info func_info = {};
 	struct bpf_prog_info info = {};
 	__u32 info_len = sizeof(info);
 	const struct btf_type *t;