Re: [RFA] "fix" a problem where a breakpoint would be associated with the wrong source

[Daniel Jacobowitz <drow@false.org>]

On Wed, Feb 01, 2006 at 05:26:30PM -0800, PAUL GILLIAM wrote:
> I ran across a problem where a breakpoint would be associated with the
> wrong source.  Not every breakpoint, just some breakpoints.  And
> changing the order of .o files on the link line would change which
> breakpoints where affected.
> 
> A 'bad' breakpoint would give the wrong source file and line number when
> it was set.  When the program was run and a bad breakpoint hit, the
> wrong source would be shown by the break and by list.  But the break
> would, in fact, be at the right place.
> 
> In debugging gdb, I narrowed it down (not the cause, just the failure)
> to find_function_start_sal().  The call to find_pc_sect_line() was
> finding the wrong sal.  I noticed that the right sal was being found
> earlier during the processing done by SKIP_PROLOGUE().  There,
> find_pc_sect_line() was being called with a null section argument.
> 
> This patch seems to "fix" the problem.  But I don't feel comfortable
> with it.
> 
> Comments?

The patch is definitely wrong, as you suspected.  We'd need to see a
testcase; it could be bogus, or partially missing, debug information.
Is the 'bad' breakpoint in a file with line numbers?

-- 
Daniel Jacobowitz
CodeSourcery