Holding Ctrl+C on Windows GHCI Prompt crashes with concurrency panic

When I hold Control-C in the GHCI prompt (on either Windows Powershell or Command Prompt), then release, the prompt stops responding. The first few keystrokes will be ignored altogether, then the next ignored intermittently.

After typing around 5 words, GHCi crashes with the following output:

ghc.exe: panic! (the 'impossible' happened)
  (GHC version 7.10.2 for x86_64-unknown-mingw32):
        thread blocked indefinitely in an MVar operation

If I don't type after holding Ctrl+C, GHCi seems to sit happily without crashing. No amount of waiting after holding Ctrl+C seems to make it recover. It does not matter whether I press return or not.

However, faster typing seems to make it crash in fewer keystrokes.

Trac metadata

Trac field	Value
Version	7.10.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	lowest
Resolution	Unresolved
Component	GHCi
Test case
Differential revisions
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Related
Blocking
CC
Operating system
Architecture