Proposal: Improved error message of "Error in array index"

Olaf Chitil O.Chitil at
Wed Nov 9 06:52:16 EST 2005

Simon Marlow wrote:

>I can explain why it happens,
>though.  The compiler has lifted out the error case into a top-level
>  x = error "Error in array index"
So cost-centre stacks are not produced for the original program written 
by the user, but for the intermediate program after optimisation. I 
understand that you want to profile the optimised version, but the fact 
that your profile does not quite match your program can be confusing. 
For debugging, however, I think that it is clear that you want your 
debugging information (cost centre stacks) to match your program, even 
if it costs you some performance.


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