How base package version relates to GHC version?

Question

Since base contains some GHC modules, it looks like it may be coupled with certain GHC release. Suppose that I want to use library that depends on base:4.8.0.0, does it mean it requires certain GHC release and I need to upgrade GHC?

Answer 1

Core library version to GHC version is a 1:N relation.

Since base contains some GHC modules, it looks like it may be coupled with certain GHC release.

base library is a core library defined as library which ships with GHC itself.

The GHC and library versions are maintained independently but the shipped library version changes are documented in each GHC release notes.

Base package haskell wiki page lists changes to shipped base library version and the GHC version where changed.

Suppose that I want to use library that depends on base:4.8.0.0, does it mean it requires certain GHC release and I need to upgrade GHC?

Mostly yes. It is not recommended to update core libraries alone though it is possible sometimes, ... by some people.

As a side note GHC does not release odd minor versions.

Also some libraries are defined by the haskell reports. However, there doesn't appear any mention of libraries.

Answer 2

Upgrading base by minor version steps might be theoretically possible sometimes. However, there is really no guarantee, and I'm not sure it's ever actually possible. Furthermore, it's hard to imagine why one might want to do so-it's not likely to be faster or easier than upgrading GHC.