diff --git a/test/run b/test/run
index 186d79b0..208199d4 100755
--- a/test/run
+++ b/test/run
@@ -20,7 +20,16 @@ if [ "$1" = "--one" ]; then
 	short=${name#[0-9][0-9][0-9]_}
 	bin=$BIN/test_$short
 	if [ ! -x "$bin" ]; then
-		printf 'SKIP %s (no binary %s)\n' "$name" "$bin" > "$prefix.status"
+		# A missing binary means an unwired test/wcc file: `make test`
+		# builds every $(TESTS) target before this runs, so the only way
+		# to get here is a .c with no Makefile rule. That used to SKIP
+		# and still count toward "all N tests passed" — 953_arrlit_slice
+		# sat dark for weeks under a green gate. Fail loud instead.
+		{
+			printf 'FAIL %s (no binary %s)\n' "$name" "$bin"
+			printf 'unwired test: add $(BIN)/test_%s to TESTS + a build rule in Makefile\n' "$short"
+		} > "$prefix.status"
+		: > "$prefix.fail"
 		exit 0
 	fi
 	if "$bin" > "$prefix.out" 2> "$prefix.err"; then