diff --git a/tests/libtest/lib557.c b/tests/libtest/lib557.c
index c9400a60c8d9289438ec70554956cc8c8a56f22d..d09b567f2fce7084278909f939345a0eae6dd931 100644
--- a/tests/libtest/lib557.c
+++ b/tests/libtest/lib557.c
@@ -219,7 +219,7 @@ static int test_signed_short_formatting(void)
 
 #if (SIZEOF_SHORT == 1)
 
-  i++; ss_test[i].num = 0x7F; ss_test[i].expected = "127";
+  i=1; ss_test[i].num = 0x7F; ss_test[i].expected = "127";
 
   i++; ss_test[i].num = 0x70; ss_test[i].expected = "112";
   i++; ss_test[i].num = 0x07; ss_test[i].expected = "7";