Re: Unable to find dynamic linker breakpoint function.

[Kris Warkentin <kewarken at qnx dot com>]

I think you're seeing two different problems here but they may have the 
same root.  Gdb may be finding the wrong glibc - that is, not the same 
one that the program is using.  Try 'info shared' to see what gdb is using.

As far as the stop goes, string::at(2) may have been inlined in which 
case the breakpoint may well be in that code.  You might want to look at 
the assembly.  Try breaking on seven, nexting to 8 and see if you get 
the same result.  Or clear the breakpoint before calling x.at(2).  
Possibly the weird break is due to the wrong libc as above though.

cheers,

Kris

Hareesh Nagarajan wrote:

> Hi,
>
> I know this question has been posted before, but I am posting this again
>
> because I don't know how to fix this warning;
>
> 1. warning: Unable to find dynamic linker breakpoint function.
> GDB will be unable to debug shared library initializers
> and track explicitly loaded dynamic code.
>
> And then, how must I fix this problem;
>
> 2. The program being debugged stopped while in a function called from 
> GDB. When the function (std::string::at(unsigned) const) is done 
> executing, GDB will silently stop (instead of continuing to evaluate the
>
> expression containing the function call).
>
> My gdb run appears below.
>
> Thanks,
>
> Hareesh
>
> PS: I'm running GDB 6.0. libstdc++ and glibc have been compiled with 
> DEBUG information.
>
> (gdb) r
> Starting program: /home/hareesh/new
> warning: Unable to find dynamic linker breakpoint function.
> GDB will be unable to debug shared library initializers
> and track explicitly loaded dynamic code.
> l
> Program exited normally.
> (gdb) l
> 1       #include <iostream>
> 2       #include <string>
> 3       using namespace std;
> 4
> 5       int main(void)
> 6       {
> 7               string x("heloo");
> 8               cout << x.at(2);
> 9       }
> (gdb) b 8
> Breakpoint 1 at 0x80488a6: file new.cc, line 8.
> (gdb) r
> Starting program: /home/hareesh/new
> warning: Unable to find dynamic linker breakpoint function.
> GDB will be unable to debug shared library initializers
> and track explicitly loaded dynamic code.
>
> Breakpoint 1, main () at new.cc:8
> 8               cout << x.at(2);
> (gdb) inspect x
> $1 = {static npos = 4294967295, _M_dataplus = {<allocator<char>> = {<No 
> data fields>}, _M_p = 0x804a05c "heloo"},
>   static _S_empty_rep_storage = {0, 0, 0, 0}}
> (gdb) inspect x.at(2)
>
> Breakpoint 1, main () at new.cc:8
> 8               cout << x.at(2);
> The program being debugged stopped while in a function called from GDB.
> When the function (std::string::at(unsigned) const) is done executing, 
> GDB will silently
> stop (instead of continuing to evaluate the expression containing
> the function call).
> (gdb)
>