Auto merge of #28042 - Jake-Shadle:master, r=steveklabnik
Auto merge of #28042 - Jake-Shadle:master, r=steveklabnik

Encountered an issue with `pacman` while going through the guide for installing the `mingw` toolchain on Windows with `msys2`, after some googling I found the [solution](https://github.com/Alexpux/MSYS2-packages/issues/163#issuecomment-73555971).

I thought it would be good to update the README so people don't get frustrated. :smiley: 

r? @steveklabnik

GBGamer/rust,aidancully/rust,graydon/rust,graydon/rust,aidancully/rust,GBGamer/rust,GBGamer/rust,GBGamer/rust,graydon/rust,aidancully/rust,graydon/rust,GBGamer/rust,aidancully/rust,aidancully/rust,GBGamer/rust,aidancully/rust,graydon/rust,graydon/rust,GBGamer/rust,GBGamer/rust