To: pgcc AT delorie DOT com
Subject: [1.1.3] genattrtab exposes optimization bug
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From: jerry AT cs DOT ucsb DOT edu (Jerry James)
Date: 26 Apr 1999 17:08:43 -0700
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Reply-To: pgcc AT delorie DOT com


I wanted to see how well pgcc can optimize itself, just to get some idea
of how trustworthy its optimizations are.  My first build, with -O6 used 
for everything, crashed when it tried to run genattrtab (with a
segmentation fault).  My experiments indicate that the problem is with
the compilation of genattrtab.c itself, although I haven't tracked it
down to a specific point in the code.  If anyone is interested in
tracking this down, here's what I know so far:

  -O3: works
  -O4: segmentation fault
  -O4 -fno-risc: works
  -O5 -fno-risc: segmentation fault
  -O5 -fno-risc -fno-omit-frame-pointer: works
  -O6 -fno-risc -fno-omit-frame-pointer: works

This is on a Pentium II-based Solaris 7 system.
-- 
Jerry James
Email: jerry AT cs DOT ucsb DOT edu
WWW:   http://www.cs.ucsb.edu/~jerry/