id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
6025	GHC Panic On Recompile	scooty-puff		"Perhaps related to `DataKinds` or `ConstraintKinds`, but on rebuild without a clean, the following error is emitted:

{{{
Building glyph-0.1...
Preprocessing executable 'glyph' for glyph-0.1...
[34 of 60] Compiling Language.Glyph.HM.InferType ( src/Language/Glyph/HM/InferType.hs, dist/build/glyph/glyph-tmp/Language/Glyph/HM/InferType.p_o )
ghc: panic! (the 'impossible' happened)
  (GHC version 7.4.1 for x86_64-unknown-linux):
	tyThingTyCon
    Data constructor `main:Language.Glyph.Type.Normal{d r3iU}'

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug
}}}
This can be recreated by building this cabal project:

https://github.com/sonyandy/glyph/tree/ghc-panic

To recreate:
{{{
git clone https://github.com/sonyandy/glyph/tree/ghc-panic

cabal configure

cabal build

touch src/Language/Glyph/HM/InferType.hs

cabal build
}}}"	bug	closed	normal		Compiler	7.4.1	fixed			Unknown/Multiple	Unknown/Multiple	Compile-time crash	Unknown	polykinds/T6025