Rollup of 5 pull requests

[frewsxcv]

• Successful merges: rustc: Stabilize the #![windows_subsystem] attribute #40870, Emit proper lifetime start intrinsics for personality slots #40908, Allow using Vec::<T>::place_back for T: !Clone #40909, Add a note about overflow for fetch_add/fetch_sub #40927, Added links to from_utf8 methods in Utf8Error #40992
• Failed merges:

[rust-highfive]

Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @aturon (or someone else) soon.

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[frewsxcv]

@bors r+

[bors]

📌 Commit 2f2509f has been approved by frewsxcv

[frewsxcv]

@bors p=10

[bors]

⌛ Testing commit 2f2509f with merge 6081e81...

[bors]

💔 Test failed - status-travis

[alexcrichton]

@bors: retry * sccache failure - #40240

…

On Sat, Apr 1, 2017 at 2:40 PM, bors ***@***.***> wrote: 💔 Test failed - status-travis <https://travis-ci.org/rust-lang/rust/builds/217609386> — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#41002 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAD95LUJn0K4MMARoooqMFjBfogZm36Nks5rrrYogaJpZM4MwlnO> .

[bors]

⌛ Testing commit 2f2509f with merge 7bd187a...

[bors]

💔 Test failed - status-travis