Re: [PATCH] remove ECOFF

["Joseph S. Myers" <joseph@codesourcery.com>]

On Mon, 19 Aug 2013, Maciej W. Rozycki wrote:

>  We have kept maintaining bare-iron MIPS PDR support in CodeBench and my 
> intent is to enable it for Linux MIPS targets, add the heuristic outlined 
> above and resurrect the old code GDB used to have with the improvements 
> included.  Without that debugging is often a challenge -- while the 
> heuristic unwinders are good enough to handle stepping in to a function 
> that has no debug information so that it's skipped over with the usual 
> `step' or `next' CLI operations (and their MI equivalents), interrupting a 
> program randomly within a function that has no debug information -- a 
> common scenario e.g. where a Linux process is sleeping in a syscall 
> invoked from stripped libc -- provides the user with no backtrace and 
> therefore no access to any local state or the ability to control execution 
> other than by instruction-level stepping (`stepi' or `nexti').

Rather than resurrecting this legacy MIPS-specific support, it would seem 
a lot better on Linux to generate .eh_frame by default (as on various 
other architectures) and phase out any remaining PDR generation there.  
For glibc 2.18 the eh_frame CFI information is present in many assembly 
sources and it could be added to the rest.

-- 
Joseph S. Myers
joseph@codesourcery.com