some small doc improvements

clippy_lints/src/overflow_check_conditional.rs

@@ -13,7 +13,6 @@ use utils::span_lint;
 /// ```rust
 /// a + b < a
 /// ```
-
 declare_lint! {
     pub OVERFLOW_CHECK_CONDITIONAL,
     Warn,

clippy_lints/src/regex.rs

@@ -11,10 +11,9 @@ use syntax::codemap::{Span, BytePos};
 use syntax::symbol::InternedString;
 use utils::{is_expn_of, match_def_path, match_type, paths, span_lint, span_help_and_lint};
 
-/// **What it does:** Checks [regex] creation (with `Regex::new`,
+/// **What it does:** Checks [regex](https://crates.io/crates/regex) creation
-/// `RegexBuilder::new` or `RegexSet::new`) for correct regex syntax.
+/// (with `Regex::new`,`RegexBuilder::new` or `RegexSet::new`) for correct
-///
+/// regex syntax.
-/// [regex]: https://crates.io/crates/regex
 ///
 /// **Why is this bad?** This will lead to a runtime panic.
 ///

clippy_lints/src/types.rs

@@ -1008,7 +1008,11 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for CharLitAsU8 {
 /// that is is possible for `x` to be less than the minimum. Expressions like
 /// `max < x` are probably mistakes.
 ///
-/// **Known problems:** None.
+/// **Known problems:** For `usize` the size of the current compile target will
+/// be assumed (e.g. 64 bits on 64 bit systems). This means code that uses such
+/// a comparison to detect target pointer width will trigger this lint. One can
+/// use `mem::sizeof` and compare its value or conditional compilation attributes
+/// like `#[cfg(target_pointer_width = "64")] ..` instead.
 ///
 /// **Example:**
 /// ```rust