[Issue 22630] New: It is possible for VS to be installed and providing VC directory without VC libraries being installed

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=22630

          Issue ID: 22630
           Summary: It is possible for VS to be installed and providing VC
                    directory without VC libraries being installed
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Windows
            Status: NEW
          Severity: critical
          Priority: P1
         Component: druntime
          Assignee: nobody at puremagic.com
          Reporter: alphaglosined at gmail.com

As of:
VS 2022
dmd 2.098.1 but may also effect going back to 2.091 as per issues 22525 and
21867.

Known environment to cause this:

For VS install with just F#.
During installer of dmd select MinGW.

During linking it is known that:
/LIBPATH:"C:\Program Files\Microsoft Visual Studio\2022\Community\VC\lib\amd64"
will be added.

It will error with:
lld-link: error: could not open 'libcmt.lib': no such file or directory

Directory that does exist:
C:\Program Files\Microsoft Visual Studio\2022\Community\VC

But not:
C:\Program Files\Microsoft Visual Studio\2022\Community\VC\lib

This may be fixable by changing getVCLibDir to check before returning that the
path returned actually exists and not just return whatever it thinks should be
the location.

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