diff --git a/main.c b/main.c
index 5627eca4..76525723 100644
--- a/main.c
+++ b/main.c
@@ -515,7 +515,7 @@ int main(int argc, char* argv[]) {
       fprintf(stderr, "Error: %s opening /dev/null\n", strerror(errno));
       exit(3);
     }
-    assert(first_file != 0 && !strcmp(first_file, "-"));
+    assert(first_file != 0 && strcmp(first_file, "-") != 0);
     if (rename(t, first_file) == -1) {
       fprintf(stderr, "Error: %s renaming temporary file\n", strerror(errno));
       exit(3);
diff --git a/tests/run b/tests/run
index bb7d0727..3250b33a 100755
--- a/tests/run
+++ b/tests/run
@@ -129,6 +129,11 @@ EOF
 printf '1\n'|./jq -ces --seq '. == [1]' >/dev/null 2> $d/out
 cmp $d/out $d/expected
 
+$VALGRIND $Q ./jq -n '0, 1, 2' > $d/a
+$VALGRIND $Q ./jq -n '3, 4, 5' > $d/b
+$VALGRIND $Q ./jq -i '.+1' $d/a $d/b
+$VALGRIND $Q ./jq -se '. == [1,2,3,4,5,6]' $d/a
+
 ## Test streaming parser
 
 ## If we add an option to stream to the `import ... as $symbol;` directive