ghc-6.4.1.20050806 (and before ghc-6.4.1.20050731) built successfully on Solaris (Sparc).

bash-2.05$ uname -a
SunOS kleopatra 5.9 Generic_118558-04 sun4u sparc SUNW,Sun-Fire-V240
bash-2.05$ gcc -v
Reading specs from /export/home/haskells/geisler/sw/lib/gcc/sparc-sun-solaris2.9/3.4.4/specs
Configured with: ./configure --prefix=/export/home/haskells/geisler/sw --with-ld=/export/home/haskells/geisler/sw/bin/ld --with-as=/export/home/haskells/geisler/sw/bin/as
Thread model: posix
gcc version 3.4.4
bash-2.05$ ld -v
GNU ld version 2.16
bash-2.05$ as -v
GNU assembler version 2.16 (sparc-sun-solaris2.9) using BFD version 2.16

ghc was configured with:

./configure --prefix=/export/home/haskells/geisler/sw --disable-opengl --disable-glut --disable-openal

To build ghc-6.4.1.20050806, I used ghc-6.4.1.20050731 which was built with Christian Maeder's binary distribution for Solaris (http://www.haskell.org/ghc/dist/stable/dist/ghc-6.4.1-sparc-sun-solaris2.tar.bz2) from June 2005.

I was able to build all our Haskell code. Some first tests were successful.