Wrong pragma parsing

If I write the following code with pragma LANGUAGE and extension concatenated, ghci complains about unrecognized pragma but loads module.

{-# LANGUAGEExistentialQuantification #-}
module TestHS where

data ShowBox = forall s.Show s => SB s
instance Show ShowBox where
  show (SB s) = show s

list :: [ShowBox]
list = [SB "sdf", SB 4, SB True, SB (Nothing::Maybe())]

If pragma is not recognized, the extension ExistentialQuantification should not be loaded and so file should not compile. Another strange thing is that when I :reload file in ghci it does not complain about pragma anymore. It is needed to close ghci and open it once again to see error about not recognized pragma.

Also I think that if pragma concatenated with following information is legal it will give ambiguity for cases like adding pragma SPECIAL with existing pragma SPECIALIZE.

Trac metadata

Trac field	Value
Version	6.10.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler (Parser)
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