diff --git a/proc/alloc.c b/proc/alloc.c
index 94af47f7..3cdb60fc 100644
--- a/proc/alloc.c
+++ b/proc/alloc.c
@@ -30,7 +30,7 @@ static void xdefault_error(const char *restrict fmts, ...) {
     va_list va;
 
     va_start(va, fmts);
-    fprintf(stderr, fmts, va);
+    vfprintf(stderr, fmts, va);
     va_end(va);
 }