fixes #13622 (#13679)

tests/arc/tstrformat.nim

@@ -0,0 +1,20 @@
+discard """
+  output: '''verstuff'''
+  cmd: "nim c --gc:arc $file"
+"""
+
+# bug #13622
+
+import strformat
+
+template necho*(args: string) {.dirty.} =
+  if getCurrentException() != nil:
+    echo args
+  else:
+    stdout.writeLine(args)
+
+proc main(cond: bool; arg: string) =
+  if cond:
+    necho &"ver{arg}\n"
+
+main(true, "stuff")