tools: bpftool: compile with $(EXTRA_WARNINGS)

Compile bpftool with $(EXTRA_WARNINGS), as defined in
scripts/Makefile.include, and fix the new warnings produced.

Simply leave -Wswitch-enum out of the warning list, as we have several
switch-case structures where it is not desirable to process all values
of an enum.

Remove -Wshadow from the warnings we manually add to CFLAGS, as it is
handled in $(EXTRA_WARNINGS).
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/bpf/bpftool/Makefile

@@ -37,7 +37,8 @@ prefix ?= /usr/local
 bash_compdir ?= /usr/share/bash-completion/completions
 
 CFLAGS += -O2
-CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wshadow -Wno-missing-field-initializers
+CFLAGS += -W -Wall -Wextra -Wno-unused-parameter -Wno-missing-field-initializers
+CFLAGS += $(filter-out -Wswitch-enum,$(EXTRA_WARNINGS))
 CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \
 	-I$(srctree)/kernel/bpf/ \
 	-I$(srctree)/tools/include \

tools/bpf/bpftool/cgroup.c

@@ -120,8 +120,8 @@ static int count_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type)
 static int show_attached_bpf_progs(int cgroup_fd, enum bpf_attach_type type,
 				   int level)
 {
+	const char *attach_flags_str;
 	__u32 prog_ids[1024] = {0};
-	char *attach_flags_str;
 	__u32 prog_cnt, iter;
 	__u32 attach_flags;
 	char buf[32];

tools/bpf/bpftool/perf.c

@@ -104,6 +104,8 @@ static void print_perf_json(int pid, int fd, __u32 prog_id, __u32 fd_type,
 		jsonw_string_field(json_wtr, "filename", buf);
 		jsonw_lluint_field(json_wtr, "offset", probe_offset);
 		break;
+	default:
+		break;
 	}
 	jsonw_end_object(json_wtr);
 }
@@ -140,6 +142,8 @@ static void print_perf_plain(int pid, int fd, __u32 prog_id, __u32 fd_type,
 		printf("uretprobe  filename %s  offset %llu\n", buf,
 		       probe_offset);
 		break;
+	default:
+		break;
 	}
 }