All commands fail unless ghc is on the PATH (master)

[snoyberg]

Steps to reproduce

1. Install latest Stack from master (1bbed48)
2. Run stack path or any other command

Expected

The command to succeed

Actual

Get an error along the lines of:

Executable named ghc not found on path: [...]

Stack version

$ stack --version
Version 1.10.0, Git revision 1bbed48cf22ecc7a3fa3ed230e1cc6354fdf809f (dirty) (6717 commits) x86_64 hpack-0.31.1

More info

The hashSourceMapData function is calling proc compilerExe ["--info"] readProcess, which seems to be where this error message is coming from. I don't know why Stack isn't using the modified process execution environment to find the appropriate GHC.

[silky]

this is what i reported here: #4465

[snoyberg]

Thanks for reporting @silky, sorry I didn't notice. @qrilka got this fixed on master now, please check it out and confirm for yourself when you have a chance.