diff --git a/string-list.c b/string-list.c
index 343cf1ca90..d8da3dd414 100644
--- a/string-list.c
+++ b/string-list.c
@@ -16,7 +16,7 @@ void string_list_init_dup(struct string_list *list)
 /* if there is no exact match, point to the index where the entry could be
  * inserted */
 static size_t get_entry_index(const struct string_list *list, const char *string,
-			      int *exact_match)
+			      bool *exact_match)
 {
 	size_t left = 0, right = list->nr;
 	compare_strings_fn cmp = list->cmp ? list->cmp : strcmp;
@@ -29,18 +29,18 @@ static size_t get_entry_index(const struct string_list *list, const char *string
 		else if (compare > 0)
 			left = middle + 1;
 		else {
-			*exact_match = 1;
+			*exact_match = true;
 			return middle;
 		}
 	}
 
-	*exact_match = 0;
+	*exact_match = false;
 	return right;
 }
 
 static size_t add_entry(struct string_list *list, const char *string)
 {
-	int exact_match = 0;
+	bool exact_match;
 	size_t index = get_entry_index(list, string, &exact_match);
 
 	if (exact_match)
@@ -68,7 +68,7 @@ struct string_list_item *string_list_insert(struct string_list *list, const char
 void string_list_remove(struct string_list *list, const char *string,
 			int free_util)
 {
-	int exact_match;
+	bool exact_match;
 	int i = get_entry_index(list, string, &exact_match);
 
 	if (exact_match) {
@@ -82,9 +82,9 @@ void string_list_remove(struct string_list *list, const char *string,
 	}
 }
 
-int string_list_has_string(const struct string_list *list, const char *string)
+bool string_list_has_string(const struct string_list *list, const char *string)
 {
-	int exact_match;
+	bool exact_match;
 	get_entry_index(list, string, &exact_match);
 	return exact_match;
 }
@@ -92,7 +92,7 @@ int string_list_has_string(const struct string_list *list, const char *string)
 int string_list_find_insert_index(const struct string_list *list, const char *string,
 				  int negative_existing_index)
 {
-	int exact_match;
+	bool exact_match;
 	int index = get_entry_index(list, string, &exact_match);
 	if (exact_match)
 		index = -1 - (negative_existing_index ? index : 0);
@@ -101,7 +101,8 @@ int string_list_find_insert_index(const struct string_list *list, const char *st
 
 struct string_list_item *string_list_lookup(struct string_list *list, const char *string)
 {
-	int exact_match, i = get_entry_index(list, string, &exact_match);
+	bool exact_match;
+	size_t i = get_entry_index(list, string, &exact_match);
 	if (!exact_match)
 		return NULL;
 	return list->items + i;
diff --git a/string-list.h b/string-list.h
index 2b438c7733..bc7f38022e 100644
--- a/string-list.h
+++ b/string-list.h
@@ -172,7 +172,7 @@ void string_list_remove_empty_items(struct string_list *list, int free_util);
 /* Use these functions only on sorted lists: */
 
 /** Determine if the string_list has a given string or not. */
-int string_list_has_string(const struct string_list *list, const char *string);
+bool string_list_has_string(const struct string_list *list, const char *string);
 int string_list_find_insert_index(const struct string_list *list, const char *string,
 				  int negative_existing_index);