windows10 64 bit ldc2 / dub issue

[kinke]

On Friday, 22 June 2018 at 21:22:20 UTC, Carl Sturtivant wrote:
> Today just moved from a working ldc2 1.8.0 to 1.9.0 by simply 
> changing my PATH. After that a freshly made default hello world 
> vibe.d application does not build.
>
> A simple hello.d builds and runs fine using ldc2 1.9.0 directly 
> i.e. without dub.
>
> dub init hello --type=vibe.d
> cd hello
> dub --force
>
> The above builds all vibe.d libraries fine, then when building 
> the application I get:
>
> Warning: no Visual C++ installation detected
> C:\Users\carl\ldc2-1.9.0-windows-x64\bin\ldc2.exe failed with 
> exit code 1.
>
> and then no further information.
>
> The selfsame warning also occurred when building with ldc2 
> 1.8.0 (and 1.4.0 prior to that, all on the same machine) but 
> the failure does not occur and the resulting application runs 
> fine.
>
> Also, when building a simple hello.d without dub, which works 
> fine, there is no warning "no Visual C++ installation 
> detected". This warning only appears with dub and not with 
> direct use of the compiler with all choices of ldc2: 1.4.0, 
> 1.8.0, 1.9.0.
>
> ldc2 1.10.0 behaves the same as 1.9.0 in the above situations.
>
> I am using the stand-alone Visual C++ Build Tools as described 
> here:
> https://github.com/ldc-developers/ldc#windows
> and this has worked fine for me with ldc2 until now. I simply 
> ran the installer for those long ago, and did nothing further.
>
> Any suggestions?

I just tried this in a 'x64 Native tools command prompt for VS 
2017' (environment variables fully set up by MSVC, no VS 
detection by LDC) and a naked cmd.exe (my system PATH and other 
env variables are pretty clean, no LDC/VS traces in there) with 
LDC 1.10 and its included dub (v1.8.1) on Win10, no warnings, no 
issues.

It smells very much like a dub issue if you experience it with 
dub only (and may have something to do with your particular 
environment); there have been no recent changes to LDC regarding 
VS detection & environment setup either.
You could give an older dub version a try; e.g., 1.8 ships with 
dub v1.7.2 (copying dub.exe to the new dir should do it). But 
it's also very strange that earlier dub/LDC combos worked despite 
the 'no Visual C++ installation detected' warning, that is 
supposed to be pretty fatal for linking. You can check out/hack 
the `bin\msvcEnv.bat` file to troubleshoot the MSVC detection.