bors e82584a77d Auto merge of #75585 - RalfJung:demotion, r=oli-obk ... Do not promote &mut of a non-ZST ever Since ~pre-1.0~ 1.36, we have accepted code like this: ```rust static mut TEST: &'static mut [i32] = { let x = &mut [1,2,3]; x }; ``` I tracked it back to https://github.com/rust-lang/rust/pull/21744, but unfortunately could not find any discussion or RFC that would explain why we thought this was a good idea. And it's not, it breaks all sorts of things -- see https://github.com/rust-lang/rust/issues/75556. To fix https://github.com/rust-lang/rust/issues/75556, we have to stop promoting non-ZST mutable references no matter the context, which is what this PR does. It's a breaking change. Notice that this still works, since it does not rely on promotion: ```rust static mut TEST: &'static mut [i32] = &mut [0,1,2]; ``` Cc `@rust-lang/wg-const-eval`		2020-09-08 05:13:42 +00:00
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src	Auto merge of #75585 - RalfJung:demotion, r=oli-obk	2020-09-08 05:13:42 +00:00
Cargo.toml	Add regex dependency to librustc_mir	2020-08-30 11:15:21 -07:00