[PATCH] libtraceeval: Fix comparing unsigned against zero

[Steven Rostedt <rostedt@goodmis.org>]

From: "Steven Rostedt (Google)" <rostedt@goodmis.org>

nr_key_types and nr_val_types are both size_t which is an unsized number.
A compare against zero is always false:

	if (teval->nr_key_types < 0)

Typecast it to signed for these comparisons.

Also change the few places the "size_t i" is used where it does:

	for (; i >= 0; i--)

as that too needs to be signed to work.

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 src/histograms.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/histograms.c b/src/histograms.c
index 96f0926f062c..42959c154a11 100644
--- a/src/histograms.c
+++ b/src/histograms.c
@@ -159,7 +159,7 @@ static size_t type_alloc(const struct traceeval_type *defs,
 {
 	struct traceeval_type *new_defs = NULL;
 	size_t size;
-	size_t i;
+	ssize_t i;
 
 	*copy = NULL;
 
@@ -196,7 +196,7 @@ fail:
 	else
 		print_err("traceeval_type list missing a name");
 
-	for (; i >=0; i--)
+	for (; i >= 0; i--)
 		free(new_defs[i].name);
 	free(new_defs);
 	return -1;
@@ -303,14 +303,14 @@ struct traceeval *traceeval_init(struct traceeval_type *keys,
 
 	/* alloc key types */
 	teval->nr_key_types = type_alloc(keys, &teval->key_types);
-	if (teval->nr_key_types <= 0) {
+	if ((ssize_t)teval->nr_key_types <= 0) {
 		err_msg = "Failed to allocate user defined keys";
 		goto fail_release;
 	}
 
 	/* alloc val types */
 	teval->nr_val_types = type_alloc(vals, &teval->val_types);
-	if (teval->nr_val_types < 0) {
+	if ((ssize_t)teval->nr_val_types < 0) {
 		err_msg = "Failed to allocate user defined values";
 		goto fail_release;
 	}
@@ -785,7 +785,7 @@ static int update_entry(struct traceeval *teval, struct entry *entry,
 	union traceeval_data *copy = entry->vals;
 	union traceeval_data old[teval->nr_val_types];
 	size_t size = teval->nr_val_types;
-	size_t i;
+	ssize_t i;
 
 	if (!size)
 		return 0;
-- 
2.40.1