Configure fails when new packages are updated

[codygman]

This frequently happens when I use cabal sandbox add-source. However it also happens when I simply create a sandboxed module, add some undefined code, change my cabal file with a new dependency, and try to C-c C-l. It fails with an error like:

Starting inferior `cabal repl' process using cabal ...
-> :set prompt "\4"
-> Prelude.putStrLn ""
-> :set -v1
<- ./mylib.cabal has been changed. Re-configuring with most recently used

<- options. If this fails, please run configure manually.

<- Resolving dependencies...

<- Configuring mylib-0.1.0.0...

<- cabal: T
<- he following package dependencies were requested
   --dependency='base=base-4.7.0.1-e4b74d27ad8c8987c63abc42a80e7335'
   however the given installed package instance does not exist.

I have to exit out of the current project and then restart it or it will keep failing at the configure step. It seems like settings are remembered and it's depending on specific installations hashes?

[gracjan]

@codygman: Hmm, I'm thinking where this problem might be coming from.

base package is integral part of GHC and is never reinstalled, updated, so it's hash never changes. Unless you use a couple of different compilers.

Have you by chance used cabal with -w option to select compiler?

[codygman]

@gracjan I didn't use cabal with the -w option to select the compiler. Are you recommending I try doing that?

[gracjan]

I thought you were using -w and that is the cause of your issues.

If you did not then I'm at a loss guessing what could be causing your
problem.

[gracjan]

@codygman, is this still a problem?