Changes made by GADT commit conflict with -O2 flag

[Simon Peyton-Jones]

Excellent point.  It exposes an infelicity in the handling of
substitutions.  I'm ruminating on it

S

| -----Original Message-----
| From: Sean Seefried [mailto:sseefried at cse.unsw.edu.au]
| Sent: 12 October 2004 08:27
| To: glasgow-haskell-bugs at haskell.org
| Cc: Simon Peyton-Jones
| Subject: Changes made by GADT commit conflict with -O2 flag
| 
| > -----------------------------------------------------------
| > -----------------------------------------------------------
| > The last 30 lines of
| > /Users/sseefried/cvs-ghc/HEAD/logs/HEAD-cmis-stage2 are
| > -----------------------------------------------------------
| > -----------------------------------------------------------
| >
| > utils/PrimPacked.lhs:244:0:
| >     Warning: foreign declaration uses deprecated non-standard syntax
| >
| > utils/PrimPacked.lhs:248:0:
| >     Warning: foreign declaration uses deprecated non-standard syntax
| >
| > utils/PrimPacked.lhs:251:0:
| >     Warning: foreign declaration uses deprecated non-standard syntax
| >
| > utils/PrimPacked.lhs:254:0:
| >     Warning: foreign declaration uses deprecated non-standard syntax
| >
| > utils/PrimPacked.lhs:257:0:
| >     Warning: foreign declaration uses deprecated non-standard syntax
| > ghc-6.3: panic! (the `impossible' happened, GHC version 6.3):
| > 	app_match: unbound tpl s{tv a1E9}
| 
| Hi all,
| 
| Believe it or not I've been compiling the GHC HEAD stage 2 compiler
| with the -O2 flag and it doesn't seem to be playing very nicely with
| the changes recently committed for the GADT feature. This panic is
| emitted by specialise/Rules.lhs
| 
| If I use the flag the -O utils/PrimPacked.lhs will still compile.
| 
| Sean