Fix Trac #2414: occurrs check was missed
authorsimonpj@microsoft.com <unknown>
Mon, 7 Jul 2008 10:32:01 +0000 (10:32 +0000)
committersimonpj@microsoft.com <unknown>
Mon, 7 Jul 2008 10:32:01 +0000 (10:32 +0000)
commita8cd39e47f464b88a556d026ccadbf70b09e51ed
treed0696aff3da807d4045f54af057cdd7e99f28b6d
parentf6d9137f8ba8427bbdad0650ec96211494f43d87
Fix Trac #2414: occurrs check was missed

This is an embarassing one: a missing occurs check meant that a type-incorrect
program could leak through.  Yikes!

(An indirect consequence of extra complexity introduced by boxy types. Sigh.)

Merge to 6.8.4 if we release it.
compiler/typecheck/TcUnify.lhs