# zypper in gzdoom gzdoom-debuginfo gzdoom-debugsource
$ ldd /usr/bin/gzdoom | wc -l
72
$ nm /usr/lib/debug/usr/bin/gzdoom.debug | wc -l
34550
$ unset DEBUGINFOD_URLS
$ gdb /usr/bin/gzdoom
// without issuing gdb "r"
(gdb) b <TAB><TAB>
// This is instant, which I would not have expected
Display all $max-completions possibilites? (y or n)

(gdb) b AA<TAB>
// This takes about 2 seconds on a i7-1135G7 CPU - and IMO that could be better

(gdb) b AActor::<TAB><TAB>
// another 2 seconds go by
Display all 123 possibilities? (y or n)

It feels like gdb does not have a std::map-like index over the names (because
that should allow for logarithmic lookup as well as lower_bound and upper_bound
on the available names).