Re: gcc: optimizations, and stack traces

[Valery Ushakov <uwe%stderr.spb.ru@localhost>]

[Summoning Krister]

On Fri, Feb 09, 2018 at 11:23:17 +0100, Maxime Villard wrote:

> There are also several cases where functions in the call tree can disappear
> from the backtrace. In the following call tree:
> 
> 	A -> B -> C -> D   (and D panics)
> 
> if, in B, GCC put the two instructions after the instruction that calls C,
> the backtrace will be:
> 
> 	A -> C -> D
> 
> This can make a bug completely undebuggable.

Does gcc actually generates code like that?  I thought that it can
delay frame pointer creation, but only until it needs to make a nested
call, to C in your example, (as in the sample I showed in another mail
to this thread).

-uwe