One of the tools I build on new unix boxes after I get a toolchain of some kind (vendor or GNU) is invariably emacs.
I've been working on Solaris 10 more lately, and found that emacs wouldn't build, and I found that odd... clearly other people had got it to build.
The interesting bit is that it'll build if you use the right options, but it'll crash when it exits. I was puzzled by this for awhile, but eventually found the answer on the tubes of the interweb. Unfortunately, I've had to recompile it now several times, both at work and home, and I keep having to rediscover this little platform-specific tidbit. Hopefully now that it's posted here I'll remember.
I gather than GCC 3.3.x puts some zero-initialized variables in the .bss segment, and that's a problem with Solaris (at least on SPARC), so the answer is to add "-fno-zero-initialized-in-bss" to $CFLAGS before configure.
I'm still working out how to compile this with Studio 11 from Sun, I'll update this when I remember the changes necessary.