fixes #11194 (#11242)

tests/compiler/tcppCompileToNamespace.nim

@@ -0,0 +1,12 @@
+discard """
+cmd: "nim cpp --cppCompileToNamespace:foo $options -r $file"
+target: cpp
+"""
+
+# Theoretically nim could just ignore the flag cppCompileToNamespace
+# and this test would pass.  Setting ``ccodeCheck`` for a c++ target
+# doesn't work.
+
+import os
+
+echo "a" / "b"