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if a variable that isn't in scope is used and main is not defined ghc freaks out

--y = 5::Double

f::Double ->Double

f x = x+y

--main = print 5

produces:

ghc: panic! (the 'impossible' happened)

(GHC version 8.0.2 for x86_64-unknown-linux):

initTc: unsolved constraints

WC {wc_insol = [W] y_axB :: t_axA[tau:1] (CHoleCan: y)}

Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug

un-commenting either line 1 or 4 causes ghc to identify the other problem correctly

Trac metadata
Trac field Value
Version 8.4.3
Type Bug
TypeOfFailure OtherFailure
Priority normal
Resolution Unresolved
Component Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC
Operating system
Architecture
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