1 files changed, 1 insertions, 1 deletions
diff --git a/arena.h b/arena.h
index 8e8b145..3887c6c 100644
--- a/arena.h
+++ b/arena.h
@@ -66,7 +66,7 @@ void arena_free(Arena *a) {
 
 void *arena_alloc(Arena *a, size_t sz, size_t align) {
 	char *p = a->beg + (-(uintptr_t)a->beg & (align - 1));
-	if (p >= a->end) FAIL_WITH_MSG("arena out-of-memory");
+	if (p + sz > a->end) FAIL_WITH_MSG("arena out-of-memory");
 	a->beg = p + sz;
 	return p;
 }