[Bug c++/98885] [modules] forward declaration of classes prevent them from being exported at the point of actual declaration

[nathan at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98885

--- Comment #9 from Nathan Sidwell <nathan at gcc dot gnu.org> ---
This is highlighting a missing diagnostic on:

export module A;

class A; // forward declaration

export class A {}; // <-- here, cannot add 'export'