Loading-related bug in Hugs 1.4 January 1998

[Bjarte Mayanja Oestvold]

Hi Hugs developers

Thanks for making a fine product!  I've been using Hugs 1.4 / January
1998 for a month now and it works just great.  Using previous versions
of Hugs I sometimes had to exit and re-enter Hugs in order to make it
re-load updated files properly -- this problem seems gone now.

The only (minor) problem I've had with the latest Hugs is also related
to loading (this problem does not occur with Hugs 1.4 / Version
970410).  

I've got a system of about 2k lines of Haskell source in several
modules.  If I launch the Hugs interpreter with default heap size
(h100000), load my system's source and start it I get an odd-looking
error:

    Program error: {renameType'_renamings'}

    Main> 

(In the message Hugs uses the names of a function "renameType'" and
one of its let-bound variables "renamings'".)

However, my system runs okay if I:
 - load the source again
 - load the source twice before starting it the first time
 - increase Hugs' heap size to h200000

Curiously, if I use heap size h100001 (i.e., 1 larger than the
default) Hugs says the following when loading my source:

    Prelude> :l Main
    ...
    Compiling          
    INTERNAL ERROR: remPat1
    List> 

I've tried to track down the cause of this behaviour, but the problem
tends to go away when I change my source, so no luck...  Fortunately
this also means that the bug no longer bothers me.  

I guess you have more pressing problems, but if you're interested I
have a snapshot of a set of files that makes the bug appear.  (My OS's
data: SunOS drue.idi.ntnu.no 5.5.1 Generic_103640-08 sun4u sparc)

Cheers,
  Bjarte