RFC 'used only once' warnings shouldn't affect (some?) internal packages

This is annoying:

$ perl -Mwarnings -e 'require Config; if (!$Config::Config{d_foo}) {
*CORE::GLOBAL::glob = sub {} }'
Name "CORE::GLOBAL::glob" used only once: possible typo at -e line 1.
Name "Config::Config" used only once: possible typo at -e line 1.

I'm thinking that anything under %CORE::GLOBAL:: and *Config::Config should
have the MULTI flag automatically set in gv.c, so this warning won't happen
for them. I can provide a patch, but perhaps there's other packages that
should have the same treatment?

Admittedly, Config has a workaround -- change the require to a 'use Config
()' and you're done. But the *CORE::GLOBAL:: doesn't -- you're stuck either
using trickery* or disabling the warning.

[*] My new favorite thing that I'll never have the chance to use: *{ +do {
no warnings "once"; \*CORE::GLOBAL::glob } } = sub {};

• RFC 'used only once' warnings shouldn't affect (some?) internal packages by Brian Fraser
• Re: RFC 'used only once' warnings shouldn't affect (some?) internalpackages by Nicholas Clark
• Re: RFC 'used only once' warnings shouldn't affect (some?) internalpackages by Ricardo Signes