https://issues.dlang.org/show_bug.cgi?id=24308

          Issue ID: 24308
           Summary: [ImportC] druntime\import\importc.h(134): fatal error
                    C1034: sal.h: no include path set
           Product: D
           Version: D2
          Hardware: x86
                OS: Windows
            Status: NEW
          Severity: enhancement
          Priority: P1
         Component: druntime
          Assignee: nobody@puremagic.com
          Reporter: andrej.mitrovich@gmail.com

Here is 'clap.c' which is the pre-processed header file from a C library: https://gist.github.com/AndrejMitrovic/427866da4d3e9cd7dc307925f9eebdfa

---
dmd -m64 -c .\clap.c
C:\Apps\DMD\dmd2\windows\bin\..\..\src\druntime\import\importc.h(134): fatal
error C1034: sal.h: no include path set
Error: C preprocess command C:\Program Files\Microsoft Visual
Studio\2022\Community\VC\Tools\MSVC\14.34.31933\bin\HostX64\x64\cl.exe failed
for file .\clap.c, exit status 2
---

In 2.105.3 this worked ok, but in 2.106.0 it fails.

I don't quite get if I'm just missing an import on my side or if it's a bug in Druntime?

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