How to run lit tests on Mac OSX without gcc?

[David Nadlinger via digitalmars-d-ldc]

On 31 Aug 2017, at 19:08, Johan Engelen via digitalmars-d-ldc wrote:
> We don't want to pass through all env variables, as it is going to 
> disrupt testing in strange ways. I take it as a very good thing that 
> Lit does not pass env vars through.

I'm not sure I'd agree with it disrupting testing any more than other 
environmental factors (OS/linker versions, etc.), but fair enough.

> We could pass through specific ones explicitly:
> ```
>   config.environmen['CC'] = os.environ['CC']
> ```

Let's do that, then – it would have been used to compile the standard 
libraries, etc. before outside of lit anyway.

  — David