Compilers	Virtual Machines	Machine-Code Translation
Portability
Source code	yes with exceptions	yes	yes
Object code	no	yes	yes
OS	only if source is available	yes if using virtual machine	yes
Device drivers	yes with modification	yes, but may require modification	yes, but may require modification
Framework	only if source is available	yes	yes
Pros	C/C++ compilers are relatively standard; optimized performance	machine independent; consistent debugging environment	high-performance, consistent debugging environment
Cons	source required; can't use CPU or platform-specific features	potential performance penalty	less efficient than native code; hardware-specific
Debug support	excellent if source is available	excellent if source is available; fair if source unavailable	excellent if source is available; fair if source unavailable
Runtime overhead	none	depends on implementation, interpretation, cache, JIT latency	cache, JIT latency
Examples	C/C++ compilers	Java, .NET CLR, Inferno	Transmeta Cruso, Transitive Technologies Dynamite