Cannot add directories with colon to include path

ezyang@sabre:~$ ls f:g
A.hi  A.hs  A.o
ezyang@sabre:~$ ghc-8.0 --make A -if:g

<no location info>: error: module ‘A’ is a package module
ezyang@sabre:~$ ghc-8.0 --make A -if\:g

<no location info>: error: module ‘A’ is a package module
ezyang@sabre:~$ ghc-8.0 --make A -if\\:g

<no location info>: error: module ‘A’ is a package module

The problem is that the colon is interpreted as a path separator.\

Of course, colons break everything forever, so you shouldn't use them. But it is still a bit unsatisfactory.

Trac metadata

Trac field	Value
Version	8.0.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	lowest
Resolution	Unresolved
Component	Compiler
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