importing a file and including it as a cli arguments leads to bad error message

[expipiplus1]

nullType.slang:

import nullTypeModule;

struct S { }

extension S : I { }

nullTypeModule.slang:

interface I { } 

slangc -stage compute tests/bugs/nullTypeModule.slang tests/bugs/nullType.slang

tests/bugs/nullType.slang(5): error 39999: ambiguous reference to 'I'
extension S : I { }
              ^
tests/bugs/nullTypeModule.slang(1): note 39999: candidate: interface I
interface I { }
          ^
tests/bugs/nullTypeModule.slang(1): note 39999: candidate: interface I
interface I { }
          ^

This "ambiguous" reference refers to the same name