[PATCH] util: constant -1 with expression of type char and allocation failure handling

[yskelg@gmail.com]

From: Yunseong Kim <yskelg@gmail.com>

This patch resolve this warning.

tools/perf/util/evsel.c:1620:9: error: result of comparison of constant
-1 with expression of type 'char' is always false
 -Werror,-Wtautological-constant-out-of-range-compare
 1620 |                 if (c == -1)
      |                     ~ ^  ~~

Add handling on unread_unwind_spec_debug_frame().
This make caller find_proc_info() works well when the allocation failure.

Signed-off-by: Yunseong Kim <yskelg@gmail.com>
---
 tools/perf/util/evsel.c                  | 2 +-
 tools/perf/util/unwind-libunwind-local.c | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 25857894c047..bc603193c477 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -1620,7 +1620,7 @@ static int evsel__read_group(struct evsel *leader, int cpu_map_idx, int thread)
 
 static bool read_until_char(struct io *io, char e)
 {
-	char c;
+	int c;
 
 	do {
 		c = io__get_char(io);
diff --git a/tools/perf/util/unwind-libunwind-local.c b/tools/perf/util/unwind-libunwind-local.c
index cde267ea3e99..a424eae6d308 100644
--- a/tools/perf/util/unwind-libunwind-local.c
+++ b/tools/perf/util/unwind-libunwind-local.c
@@ -390,6 +390,11 @@ static int read_unwind_spec_debug_frame(struct dso *dso,
 			char *debuglink = malloc(PATH_MAX);
 			int ret = 0;
 
+			if (debuglink == NULL) {
+				pr_err("unwind: Can't read unwind spec debug frame.\n");
+				return -ENOMEM;
+			}
+
 			ret = dso__read_binary_type_filename(
 				dso, DSO_BINARY_TYPE__DEBUGLINK,
 				machine->root_dir, debuglink, PATH_MAX);
-- 
2.44.0