PCC now builds and generates valid code (with a few quirks and such) on AMD64. The support libraries also have floating point support and a proper C support unit. Now that amd64 hosts are enabled, anyone that would like to test it feel free to do so. Bug reporting is a big thing right now, so if you have the time, try it out and give some feedback.
(Disclaimer: I'm not a member nor affiliate of the PCC project, but I do really wish for it to succeed.)
Portable C Compiler
Re: Portable C Compiler
One of my goals of AlloyOS was to build cleanly with BSD tools and GNU tools, including pcc, so it is definitely suitable for system programming.. just a little difficult to configure a crosscompiler using a custom C library(as in, I never got it to work without -L hackery)