Re: gdb 6.3 C++ breakpoint in constructor/destructor patch

[Daniel Jacobowitz <drow@false.org>]

On Sun, May 01, 2005 at 08:32:12PM +0200, Thomas Maier wrote:
> Hello,
> 
> I want to supply a patch for the released gdb 6.3, that fixes partially  
> the gdb bugs
> 
> gdb/1091: Constructor breakpoints ignored
> gdb/1193: g++ 3.3 creates multiple constructors: gdb 5.3 can't set  
> breakpoints
> 
> I was really confused, why my programs to not stop at the breakpoint in  
> constructor/destructors. Now i know, it is not the fault of my programs ;)  
> Since this anoying problem seems to be in gdb since the gcc 3.x release, i  
> guess, no one else a) has this problem (i don't believe so) or b) will not  
> fix it. So i did it ;)
> 
> This modification is only made for commands like "break  
> [source]:<lineno>". For C++ constructors and destructors, the patch  
> creates more than one breakpoint at the source at lineno, but each  
> generated breakpoint will have another address!
> 
> NOTE: this is only a simple "hack". I have spent only one day to get into  
> gdb source code and do the modification.
> It would be better, to create only one breakpoint in such C++ constructors  
> and destructors and assign multiple addresses to it. But this needs a huge  
> modification of gdb, i guess ;)

This is not a very useful change, because it only handles the case
where everything at a particular line is in the same symtab.  Often
this will not be the case.

If you take a look at the archives for the list, you will find a lot of
discussion on this subject - as well as a prototype patch I posted
earlier this year.  That patch may be good enough for your needs, since
it handles the file:lineno case.  But it isn't done yet, and I haven't
had time to go back to it yet.

-- 
Daniel Jacobowitz
CodeSourcery, LLC