build sytem feature request: persist warnings

I often have this pattern: I hack on GHC in devel2 mode, introducing a few changes that cause warnings all over the place (usually related to imports). I ignore them while I work on the feature.

Now I want to clean the warnings up. I basically only have one option: Switch the settings to make warnings errors, make clean, re-build everything, see where it aborts, fix it, restart the build.

This is annoying.

I would prefer if the build system (in any more) would keep, for every file, the output of the compiler on disc, e.g. with a suffix of .comp-out or something. This way, after a complete build, even without -Werror, I can simply run cat **/*.comp-out (or whatever suffix is suitable), fix all these error in one go, and be done with it.

Trac metadata

Trac field	Value
Version	8.0.1
Type	FeatureRequest
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Build System
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture

changed weight to 5

added Tfeature request Trac import labels

Doesn't directly solve your problem, but https://github.com/ezyang/ghc-shake logs warnings to persistent files so that you can view them later. They get stored in *.log files, so you can print them all out with find dist -name "*.log" -exec cat {} \; or something like that.

The new Hadrian build system has been merged. Relabeling the tickets concerning the legacy make build system to prevent confusion.

Trac metadata

Trac field	Value
Component	Build System → Build System (make)

added Pnormal label