False positive: similar_names gets confused by macro param names

[illicitonion]

Here's a minimal playground link: https://play.rust-lang.org/?gist=a1333019fbad19ebeb92f00abd6a0e64&version=nightly&mode=debug&edition=2015

The variable needs to specifically called args (arg is fine),

Possibly a duplicate of #2651 and/or #2927

[flip1995]

Yep dup of #2927. Thanks for reminding!

Thanks for the minimal example.