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"Cannot access memory at address 0x175f80"

Hi. I'm debugging a C++ tool (called apple) that's loaded as a dynamic library into a C - or C++ program (called orange) . Apple is compiled with g++ 3.3.1, binutils 2.14, and debugging symbols are enabled. Orange is a big unknown (meaning: I don't know how it was compiled) and it has no debugging symbols. The gdb version is 5.3

Here are the flags used to compile Apple:
# -gdwarf-2 -g3 used to enable stepping through macro execution under gdb 5.3 The explanation's under gdb 5.3 release notes.
Compile:g++ -std=c++98 -Wall -DLINUX -gdwarf-2 -g3 -D__USE_GNU -D_GNU_SOURCE -fPIC file_name.cpp

g++ -shared $(LIBS) $(OBJSCHEF) $(PLIOBJSVCS_PLI) InterfaceObjectVCS_PLI.o -o $@ -lc gdwarf-2 -g3 -fPIC
g++ -MD -std=c++98 -shared -lc -gdwarf-2 -g3 -fPIC <object files> -o

When I go to debug apple, I run "gdb <program name>", then use the "add-symbol-file <apple's path & filename> -readnow" gdb comman to load the symbols from apple. From there, I can set breakpoints in C++ class methods, no problem. But, there is 1 function (so, non-OO code), where if I try to set a breakpoint, I get the following:

   (gdb) break nc_signal_raised
Cannot access memory at address 0x175f80

   If I do an "nm" on the library, I get:
   00175f80 T nc_signal_raised

Indicating that the address read by gdb is correct.

On a related, but less important note, when use ddd to debug & go to a source file, I always get: "<src_file_name>" is at address 0x10f5f0 <part_of_src_file_name> but contains no code.

And yet I can set breakpoints or step through the code. What's going on?

Any help you can offer will be appreciated. I've been working on this for 2 weeks, read every posting or piece of documentation I can find. I'm at my wits' end!

         Andrew Greenlaw

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