Auto merge of rust-lang#30075 - kyeah:mac-span, r=sanxiyn

Fixes rust-lang#28424 (item macros), rust-lang#30067 (impl item macros), and pattern macros.

1.4.0 release

1.3.0 release

1.2.0 release

1.1.0 release

1.0.0 release

1.0.0-alpha.2 release

1.0.0-alpha release

0.12.0 release