I found that compiling galeon and mozilla with the "-march=pentium3 -O2" CFLAGS will make galeon very instable. After some experimenting with galeon2 I tried to use different CFLAGS for mozilla and galeon. Using "-march=i686 -O" makes it rock stable again. I didn't try to find out whether or not -O2 also works, but both override to use -O3. My guess is that in some way galeon triggers a bug in gcc.
Ok, but dont you think you should rather report this with the gcc guys ?