Bump version to 1.48 and update cfg(bootstrap)s

[pietroalbini]

r? @Mark-Simulacrum

[pietroalbini]

Also opened rust-lang/stdarch#885 to eventually remove the cfg(not(bootstrap)) from stdarch.

[Mark-Simulacrum]

@bors r+ p=1

[bors]

📌 Commit 3e16d4a has been approved by Mark-Simulacrum

[bors]

⌛ Testing commit 3e16d4a with merge fe8b2dfab7b2bef915a81d82fd83979c5e197015...

[rust-log-analyzer]

The job dist-mips64-linux of your PR failed (pretty log, raw log). Through arcane magic we have determined that the following fragments from the build log may contain information about the problem.

Click to expand the log.

   Compiling addr2line v0.13.0
[RUSTC-TIMING] addr2line test:false 0.362
[RUSTC-TIMING] gimli test:false 4.050
[RUSTC-TIMING] object test:false 7.975
error[E0658]: `#[doc(spotlight)]` is experimental
    |
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488 | #[doc(spotlight)]
    |
    |
    = note: see issue #45040 <https://github.com/rust-lang/rust/issues/45040> for more information
    = help: add `#![feature(doc_spotlight)]` to the crate attributes to enable

error[E0658]: `#[doc(spotlight)]` is experimental
     |
     |
1241 | #[doc(spotlight)]
     |
     |
     = note: see issue #45040 <https://github.com/rust-lang/rust/issues/45040> for more information
     = help: add `#![feature(doc_spotlight)]` to the crate attributes to enable
error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0658`.
[RUSTC-TIMING] std test:false 1.720
---
== clock drift check ==
  local time: Wed Aug 26 16:37:25 UTC 2020
  network time: Wed, 26 Aug 2020 16:37:25 GMT
== end clock drift check ==
##[error]Process completed with exit code 1.
Terminate orphan process: pid (2759) (node)
Terminate orphan process: pid (2787) (python)

I'm a bot! I can only do what humans tell me to, so if this was not helpful or you have suggestions for improvements, please ping or otherwise contact @rust-lang/infra. (Feature Requests)

[bors]

💔 Test failed - checks-actions

[Mark-Simulacrum]

It also looks like PR CI flaked on this somehow, but presumably unrelated?

[ollie27]

It looks like

rust/library/std/src/lib.rs

Line 250 in 1f2dd3b

#![cfg_attr(not(bootstrap), feature(doc_spotlight))]

was missed which explains the CI failure.

[pietroalbini]

Woops.

@bors r=Mark-Simulacrum

[bors]

📌 Commit 1b6590c has been approved by Mark-Simulacrum

[bors]

⌛ Testing commit 1b6590c with merge 118860a...

[bors]

☀️ Test successful - checks-actions, checks-azure
Approved by: Mark-Simulacrum
Pushing 118860a to master...