id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
4371	ghc panic: ToDo: Match.viewLExprEq	mafo		"The attached test-case triggers a

ghc: panic! (the 'impossible' happened)
  (GHC version 7.0.0.20100924 for x86_64-unknown-linux):
        ToDo: Match.viewLExprEq

this is a regression from 6.12.3 where there was no problem.

In the function Match.viewLExprEq
one case is not defined
however the comments say viewLExprEq may safely return False,
so this is bug is probably trivial to fix ?

The testcase uses a combination of ViewPatterns
and a cast from Data.Typeable."	bug	closed	normal		Compiler	7.1	fixed		fontaine@…	Unknown/Multiple	Unknown/Multiple	Compile-time crash		deSugar/should_compile/T4371