Trouble interfacing with C/C++ single-header library

[sls1005]

I'm not a Windows user, but...
    
    
    cl : Command line warning D9002 : ignoring unknown option '-lstdc++'
    
    Run

means vcc doesn't understand the options of gcc. You need to find the `-l` 
equivalent on vcc.
    
    
    cl : Command line warning D9024 : unrecognized source file type 
'dll\x64\WebView2Loader.dll', object file assumed
    dll\x64\WebView2Loader.dll : fatal error LNK1107: invalid or corrupt file: 
cannot read at 0x2E8
    
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means it tried to link the dll as a .obj but failed.

The solution may be:
    
    
    when not defined(vcc):
      discard #The -l equivalent
    else:
      {.passL: "-lWebView2Loader".}
    
    Run