I had a little time on my hands this afternoon, so I stole the Clang/LLVM demo
and modified it to allow compiling for several other targets:
http://ellcc.org/demo
I did notice one flaw in the LLVM demo, there doesn't seem to be a way to
upload a file to compile, at least with Firefox. I modified the cgi script
slightly to clear the $source variable if a upload file has been selected.
-Rich
Hi Richard,
I had a little time on my hands this afternoon, so I stole the Clang/LLVM demo
and modified it to allow compiling for several other targets:
Demo Page Information
does it use the correct header files for the target etc?
Ciao, Duncan.
Yes, it does. The header files are from my port of the NetBSD C library.
I'm tempted to add an option to execute the result under QEMU, but I shudder
to think about the security holes that would open. 
-Rich
We actually do have a safe way to run arbitrary native code. See
http://weegen.home.xs4all.nl/eelis/geordi/ . This is what
http://ideone.com/ and http://codepad.org/ use for safely running
code. Along with clang-bot in the #llvm irc channel.
- Michael Spencer