possible compiler bug in Irix3.2?

[Mark Moraes]

The program giftoppm in the pbmplus distribution (part of X.V11R4, in
contrib/pbmplus) when compiled with -O, doesn't work on any of the six
GIF images I tried, but produces an error like:

./giftoppm: ../../K3900204.GIF is a corrupt GIF file (unblock)

When just the file ppm/giftoppm.c is compiled with -g (all the libraries
are still with -O), it works fine.

[I can send you the source code, and a sample GIF file if you can't
 reproduce this]

	Mark.