Csmith is a tool that can generate random C programs that statically
and dynamically conform to the C99 standard. Thus, it is useful for
stress-testing compilers, static analyzers, and other tools that
process C code. Csmith has found bugs in every tool that it has
tested, and over the last several years we have used it to find
and report more than 350 previously-unknown compiler bugs.

WWW: http://embed.cs.utah.edu/csmith/