<<loop>> ing program with ghc-7.0.1

[maeder]

I've got a (unfortunately large) program that terminates with <<loop>> if compiled with ghc-7.0.1 but works as expected with ghc-6.12.3 (and ghc-6.10.4).

In order to reproduce this, install the two cabal packages programatica-1.0.0.1 and hana-0.97 (not on hackage)

 http://www.informatik.uni-bremen.de/agbkb/forschung/formal_methods/CoFI/hets/src-distribution/versions/programatica-1.0.0.1.tar.gz

 http://www.informatik.uni-bremen.de/agbkb/forschung/formal_methods/CoFI/hets/src-distribution/versions/Hana-0.97.tar.gz

(I'll try to attach this archives.)

Apply the installed program "hana" to the file "Dummy.hs" inside the hana-0.97 package.

The expected output is:

{-

scope:

-}
module Dummy where

The output produced by hana created by ghc-7.0.1 is

hana: <<loop>>

Some tracing indicated that something goes wrong in the programatica module ScopeModule?.

The original problem is reported here:  http://trac.informatik.uni-bremen.de:8080/hets/ticket/884

[maeder]

programatica cabal package

[maeder]

cabal package for test binary hana

[simonpj]

Thank you! I am embarassed to say that turns out that test T3731 is failing in the same way, and it's a nice small program. But we didn't spot it because it's not part of our daily validate, although it is a regression test. We must try harder to run *all* the regression tests before making a release.

Anyway, first thing is to fix the T3731 bug, and then we can see if that fixes Hets.

Simon

[simonpj]

I've finally fixed #3731, so I hope that also fixes Hets. [I'm still dissatisfied with the solution, but it works.] Can you try (the HEAD)? I'm pretty hopeful that it'll fix your problem. It'll turn into 7.0.2.

Simon

[maeder]

Yes, thanks a lot! It works with GHC 7.0.2 Release Candidate 1 ghc-7.0.1.20101215.

[simonpj]

Great. We're still not 100% happy with the code, so are working on yet another iteration. We'll commit a patch in a week or two, and it'd be great if you could re-test then. (but we probably won't disturb the 7.0 branch)

Simon