SV: Pruning libgcj

[Øyvind Harboe <oyvind dot harboe at zylin dot com>]

> > How can GCJ not to link with libgcj?
> >
> > I was toying with the idea of using something like jclassinfo from sourceforge to list all the
> > class files required starting at --main and then compiling only those. I'm expecting that
> > this should discover almost all the classes required for the build.
>
>It won't.
>
>The linker already only links in classes for which there is a direct
>reference in your program or libgcj startup.  If you use the command
>-Wl,-Map,myprog.map command while building your program you'll see how
>this works.

Ah. I see. I could use this trick for my app. I have serveral large .jars
for which I only use a subset for the native parts, currently the entire .jars
are linked into the executable.

Here is a demonstration of size savings when applied to Mohans HelloSWT


gcj -s -o HelloSWT.exe -fjni --main=HelloSWT swt_noawt.jar HelloSWT.java

->

helloswt.exe 3,5MB

\thisiscool-gcc\gcc-3.3\bin\gcj -s -o HelloSWT2.exe -fjni --main=HelloSWT --classpath=swt.jar HelloSWT.java -lswt


helloswt.exe 2,7MB


Øyvind