ghc and ghci differs in deailing with "undefined" with I/O

This program:

main = putStrLn ("x == " ++ undefined)

produces the following expected output with ghci:

x == *** Exception: Prelude.undefined

but when compiled with ghc and run, it gives:

$./a.out 
a.out: Prelude.undefined

we observed this in all the way back to ghc6.2.1; possibly earlier.

The semantics of error reporting in combination with I/O is murky; admittedly laziness is observable at the top-level when errors are reported. But at least ghc and ghci should do the same thing. And the behavior of ghci seems to be more appropriate.

Thanks!

Jeff Lewis and Levent Erkok

Trac metadata

Trac field	Value
Version	6.6.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	jeff@galois.com, levent.erkok@galois.com
Operating system	Unknown
Architecture	Unknown