Merge commit 'b52fb5234cd7c11ecfae51897a6f7fa52e8777fc' into clippyup

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diff --git a/src/docs/debug_assert_with_mut_call.txt b/src/docs/debug_assert_with_mut_call.txt
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+++ b/src/docs/debug_assert_with_mut_call.txt
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+### What it does
+Checks for function/method calls with a mutable
+parameter in `debug_assert!`, `debug_assert_eq!` and `debug_assert_ne!` macros.
+
+### Why is this bad?
+In release builds `debug_assert!` macros are optimized out by the
+compiler.
+Therefore mutating something in a `debug_assert!` macro results in different behavior
+between a release and debug build.
+
+### Example
+```
+debug_assert_eq!(vec![3].pop(), Some(3));
+
+// or
+
+debug_assert!(takes_a_mut_parameter(&mut x));
+```
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