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Date: Sat, 26 Jul 1997 11:00:44 -0400 (EDT)
From: "Alex.Boisvert" <boia01@castor.GEL.USherb.CA>
To: freebsd-hackers@freebsd.org
Subject: gdb and shared libraries
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Hello all hackers -

I'm trying to port the JDK 1.1.2 to FreeBSD and I am having a few 
difficulties with shared libraries.

The VM gets a segmentation faults when going through the 
_GLOBAL_OFFSET_TABLE_ to execute a function in a dynamic library (in this 
case, libawt_g.so).

The libawt_g.so library is loaded via a dlopen() call.  In gdb, I get the 
following output after the library is loaded and the VM crashed:

---- cut here -----

Program received signal SIGSEGV, Segmentation fault.
0x0 in ?? ()
(gdb) info sharedlibrary
>From        To          Syms Read   Shared Object Library
0x0807a000  0x0808a000  Yes         /usr/libexec/ld.so
0x08091000  0x080ab000  Yes         /usr/lib/libm.so.2.0
0x080aa000  0x081a5434  Yes         /usr/X11R6/lib/libXm.so.1.2
0x081a5000  0x081e7000  Yes         /usr/X11R6/lib/libXt.so.6.0
0x081e6000  0x081f0000  Yes         /usr/X11R6/lib/libXext.so.6.1
0x081ef000  0x082851a0  Yes         /usr/X11R6/lib/libX11.so.6.1
0x08285000  0x082ef710  Yes         /usr/lib/libc.so.3.0
0x09403000  0x0946552c  No          
/home/alex/jdk/javasrc/build/lib/i386/green_threads/libawt_g.so
(gdb) 

------ cut here ------

Notice the "No" for libawt_g.so in the column "Syms Read".  What does 
this mean???

Have I forgotten to do something after dlopen()?

Regards,
Alex.

PS:  I am using dlsym() to get the address of the function.