[PR debug/45531] skip debug insns in cfglayout:fixup_reorder_chain

[Eric Botcazou]

> We don't hit this very often because debug insns aren't emitted without
> optimization unless explicitly requested, and with optimization this
> seems not to arise.  Anyhow, it's easy enough to fix the code so that,
> even if it arises, we don't misbehave.

This block of code is conditionalized on !optimize.

> Regstrapping on x86_64-linux-gnu.  Ok to install?

OK, thanks.

-- 
Eric Botcazou