[SLL] linking - calling C++ code from Java using SWIG

[Mathew D. Watson]

SWIG is awesome. I am amazed as I learn what it does, but the learning 
curve has been steep. Yesterday I ran into a knot that I hope you folks 
can help me untangle.

I have a java program that calls a c++ library from a separate project. 
The command line is as follows, and the code runtime links against a 
library I will call lib_abc.so that is sitting in the current directory.

$ java -Djava.library.path=. main

I originally got this error message.

java: symbol lookup error: undefined symbol: _Z8VVGCamera4open...

The symbol name was real long, and I saw it when I ran nm on the library 
file. The library was created using

$ ld -r a.o b.o -o lib_ab.a
$ g++ -shared c.o -o lib_abc.so -L. -l_ab

I managed to eliminate the error by creating the .so using

$ g++ -shared a.o b.o c.o -o lib_abc.so

Can someone explain why the symbol was missing from the first library 
and not from the second one? In particular, why did I get the error when 
nm showed that the symbol was present?

How can I modify the first g++ line so it correctly links against the 
static library lib_ab.a?

I am pretty sure the long symbol name is called a "mangled" name. Is 
there a way to get nm to produce unmangled symbol names? Is there a 
better tool that I can use to debug this sort of problem?

Mat