Compiler Bug using D interface file for its intended purpose

[Rambutan]

On Tuesday, 8 September 2026 at 07:34:09 UTC, Richard (Rikki) 
Andrew Cattermole wrote:
> On 08/09/2026 6:31 PM, Rambutan wrote:
>> This is apparently a bug, as D interface files containing only 
>> simple type definitions to replace C header files in D source 
>> like di.di are supposed to behave like header files.
>
> No they are not.
>
> D generates metadata that must be compiled in.
>
> .di files can only exist as derivatives of D files that have 
> been linked in.

Ah, I see! Does this mean that officially .di files are not 
intended as a mechanism to provide C header file information to 
D, and so such a use is a technical exercise pushing the envelope?

This use of .di files with C is the only one I have encountered 
in practice, and they have been generated automatically from C 
header files and edited to smooth out any wrinkles. Until this 
encounter with doubles in structs this has all worked fine with 
no compilation of the .di file.