Re: [PATCH] debug/108772 - ICE with late debug generated with -flto

[Jeff Law <jeffreyalaw@gmail.com>]

On 3/1/23 06:07, Richard Biener via Gcc-patches wrote:
> When combining -g1 with -flto we run into the DIE location annotation
> machinery for globals calling dwarf2out_late_global_decl but not
> having any early generated DIE for function scope statics.  In
> this process we'd generate a limbo DIE since also the function scope
> doesn't have any early generated DIE.  The limbo handling then tries
> to force a DIE for the context chain which ultimatively fails and
> ICEs at the std namespace decl because at -g1 we don't represent that.
> 
> The following avoids this situation by making sure to never generate
> any limbo DIEs from dwarf2out_late_global_decl in the in_lto_p path
> but instead for function scope globals rely on DIE generation for
> the function to output a DIE for the local static (which doesn't
> happen for -g1).
> 
> I explored a lot of other options to fix this but in the end this
> seems to be the most spot-on fix with the least risk of unwanted
> effects.
> 
> LTO bootstrapped on x86_64-unknown-linux-gnu (running into PR108984),
> bootstrapped and tested on x86_64-unknown-linux-gnu.
> 
> OK?
> 
> Thanks,
> Richard.
> 
> 	PR debug/108772
> 	* dwarf2out.cc (dwarf2out_late_global_decl): Do not
> 	generate a DIE for a function scope static when we do
> 	not have a DIE for the function already.
> 
> 	* g++.dg/lto/pr108772_0.C: New testcase.
OK.
jeff