[Bug] dmd -H app.d fails with debug import; on Windows 11 and WSL2 Ubuntu

[lempiji]

Overview

When compiling the minimal reproduction code below, dmd fails with return code 1 on Windows 11 and with exit code 11 (segmentation fault) on Ubuntu via WSL2. In both environments, I expect a .di file to be generated, but it is not. No error message is displayed.

Minimal Reproduction Code

app. d:

debug import core.stdc.stdio;

void main() { }

Command:

dmd -H app.d

Additional Investigation

• Removing the debug keyword allows compilation to succeed and produces a .di file.
• The same behavior is reproducible with other import statements (e.g. debug import std.algorithm.searching;), while regular import works as expected.
• This issue can be reproduced when using dub to reference the "during" library, because the problematic code is written inside the source code of the "during" library.

Expected Result

• A .di file should be generated correctly

Actual Result

• Windows 11: Return code 1, no error message
• WSL2 Ubuntu: exit code 11 (segmentation fault), no error message
• No .di file is produced in either case

Environment

• OS: Windows 11, WSL2 Ubuntu
• dmd version: v2.111.0
• dmd --version output:

  DMD64 D Compiler v2.111.0
  Copyright (C) 1999-2025 by The D Language Foundation, All Rights Reserved written by Walter Bright
  

Other Notes

• No error message is displayed

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Please review and advise on possible solutions or fixes.

[ibuclaw]

Duplicate of #21406