View Full Version : CMU Common Lisp Compiling

July 28th, 2008, 05:52 PM
When compiling CMU Common Lisp, can you compile to executable machine code or is it byte code that Lisps then executes?

Can you provide a link to an example of either or both?

July 28th, 2008, 06:02 PM
To compile:

compile-file ("/pathtofile.lisp")
Then load the file:

load ("/pathoffile.lisp")
CMUCL Documentation (http://www.cons.org/cmucl/doc/index.html)

July 28th, 2008, 06:20 PM
That didn't answer my question.

Is compilation like Java's or C's?

July 28th, 2008, 06:32 PM
Common Lisp implementations do not have a compiler, it's not the same as a C++,Java,etc. compilers where it spits out raw machine language which will link into a native binary.. You still have to invoke the main Lisp binary and tell it to load and execute the FASL.

July 28th, 2008, 06:54 PM
Both SBCL and CMUCL will compile to native machine code. I think SBCL compiles everything including things you type in the REPL, while CMUCL has both a compiler and an interpreter (don't quote me on that though :)). Lisp is different from other languages in that you need the entire lisp system available at run-time. You can either achieve this by loading compiled fasl files into your lisp system, or you can use a function like sbcl's save-lisp-and-die to create a binary executable like you would in any other compiled language.

July 28th, 2008, 07:07 PM
... the only nasty problem being that save-lisp-and-die saves everything so you get a huge binary :( There is no tree-shaker unfortunately there...

July 28th, 2008, 07:18 PM
Clisp produces much smaller binaries than SBCL or CMUCL, although they are still pretty huge when compared with other languages. However using GZip I was able to compress a 15.8MB clisp program all the way down to just 2.42MB.

July 28th, 2008, 09:50 PM
I thought CLISP only produced byte code. Am I misunderstanding something or is it just old information?