1 files changed, 1 insertions, 1 deletions
diff --git a/stm/string0.c b/stm/string0.c
index d67c5f2b17..4899e7b0f5 100644
--- a/stm/string0.c
+++ b/stm/string0.c
@@ -34,7 +34,7 @@ void *memset(void *s, int c, size_t n) {
     return s;
 }
 
-int strlen(const char *str) {
+size_t strlen(const char *str) {
     int len = 0;
     for (const char *s = str; *s; s++) {
         len += 1;