You can edit this page using wiki syntax for markup.

Article contents:[[toc:]] == Reducing the size of a compiled executable === Generating the smallest possible, self-contained executable Here is a small demonstration for creating the smallest possible (while still self-contained) executable. A UNIX-like environment is assumed. A simple hello-world program: <enscript highlight=scheme> (import scheme) ;; required due to -explicit-use later on (display "Hello, world!\n") </enscript> You need the files {{library.c}}, {{runtime.c}}, {{build-version.c}}, {{chicken.h}} from the CHICKEN source distribution. In addition, you need the generated {{chicken-config.h}} file for your target platform (which can be done with {{make chicken-config.h}}, optionally with a {{PLATFORM}} passed in). First we generate {{hello.c}} from {{hello.scm}}: $ chicken hello.scm -explicit-use The option {{-explicit-use}} (note the single dash) tells the compiler not to link in the evaluator and other compilation units, since we just want the basic Scheme library (and the runtime system). The compiler is smart enough to know what compilation units to add based on any {{import}} statements being used. Now we compile {{hello.c}}, the runtime system in {{runtime.c}}, the core library {{library.c}} and build version information {{build-version.c}} into a single executable: $ gcc hello.c runtime.c library.c build-version.c -Os -fomit-frame-pointer -fno-strict-aliasing -DHAVE_CHICKEN_CONFIG_H -o hello -lm $ strip hello $ ./hello Hello, world! $ size hello text data bss dec hex filename 287958 536 12876 301370 4993a hello This program is now fully self-contained: $ ldd hello linux-gate.so.1 => (0xffffe000) libm.so.6 => /lib/tls/libm.so.6 (0x4002e000) libc.so.6 => /lib/tls/libc.so.6 (0x40050000) /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x40000000) You can also try using the GNU Autotools with compiled code. Not all functionality provided by {{library.scm}} may be required, though. It is possible to use a custom library: <enscript highlight=scheme> ;;;; lib.scm (define (##sys#interrupt-hook reason state) #f) (define (##sys#error-hook code loc . args) (##core#inline "C_halt" "error")) </enscript> $ csc -c hello.scm -x -uses library $ csc -c lib.scm -raw -x -O2 -d0 $ gcc -c runtime.c -Os -fomit-frame-pointer -fno-strict-aliasing -DHAVE_CHICKEN_CONFIG_H $ gcc hello.o runtime.o lib.o -Lchicken -lm Using this library will generate an even smaller executable. Since you will need some library functions it will be necessary to copy parts of the original {{library.scm}} into your custom library. Doing this will require some knowledge of the CHICKEN internals. -- Performing the compile above takes about 30sec for me. It seems that this can be sped up by precompiling {{runtime.c}} and {{library.c}} $ gcc -c runtime.c library.c build-version.c -Os -fomit-frame-pointer -fno-strict-aliasing -DHAVE_CHICKEN_CONFIG_H then compile hello like so: $ gcc hello.c runtime.o library.o build-version.o -Os -fomit-frame-pointer -fno-strict-aliasing -o hello -lm -- Question: why is this so much smaller than compiling statically with {{libchicken.a}}? Because we also link in at least the extras unit (unless {{-explicit-use}} is given) with {{libchicken.a}}. Question: How about any eggs I might be using? === OS X On PowerPC OS X, adding {{-C -mdynamic-no-pic}} to csc's options (Or passing {{-mdynamic-no-pic}} directly to gcc) will reduce the size of executables and other compiled files that aren't going to be dynamically loaded. Description of your changes:

I would like to authenticate

Spam control

What do you get when you subtract 17 from 9?