[Larceny-users] understanding compiler messages

[William D Clinger]

Sven Hartrumpf wrote:

> I am porting a large R5RS program to R7RS, module by module.
> But I am stuck at the following cryptic message:
> 
> > rlwrap larceny -r7rsc
> Larceny v0.98+ "General Ripper" (Jan 12 2016 13:24:38, precise:Linux:unified)
> larceny.heap, built on Di 12. Jan 13:27:54 CET 2016
> 
> > (import (larceny compiler))
> 
> > (compile-file "general.sld")
> Compiling general.sld
> Reading larceny.scm
> Reading general.scm
> 
> 
> Error: unhandled condition:
> Compound condition has these components: 
> #<record &assertion>
> #<record &who>
>     who : "car"
> #<record &message>
>     message : "car: not a pair: #f \n"
> 
> Entering debugger; type "?" for help.

This is clearly a bug in Larceny's module/macro expander.  From
the backtrace, it looks like it's a bug in the compress procedure,
so it's probably related to Larceny bug tickets #733 and #740.

I'm going to have to take some time and figure out what's wrong
with that compress procedure.  I don't know whether there was a
latent bug in that procedure that only started to show up or be
reported in v0.98, or whether the changes I made for R7RS are
causing it to be passed some incorrect inputs.

I appreciate the improvement you suggested for HOWTO-BUILD, and
have made that change.

Will