llvm-project/clang-tools-extra/clang-tidy/bugprone/IncorrectRoundingsCheck.h

40 lines
1.5 KiB
C++

//===--- IncorrectRoundingsCheck.h - clang-tidy -----------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_INCORRECTROUNDINGSCHECK_H_
#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_INCORRECTROUNDINGSCHECK_H_
#include "../ClangTidy.h"
namespace clang {
namespace tidy {
namespace bugprone {
/// \brief Checks the usage of patterns known to produce incorrect rounding.
/// Programmers often use
/// (int)(double_expression + 0.5)
/// to round the double expression to an integer. The problem with this
/// 1. It is unnecessarily slow.
/// 2. It is incorrect. The number 0.499999975 (smallest representable float
/// number below 0.5) rounds to 1.0. Even worse behavior for negative
/// numbers where both -0.5f and -1.4f both round to 0.0.
class IncorrectRoundingsCheck : public ClangTidyCheck {
public:
IncorrectRoundingsCheck(StringRef Name, ClangTidyContext *Context)
: ClangTidyCheck(Name, Context) {}
void registerMatchers(ast_matchers::MatchFinder *Finder) override;
void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
};
} // namespace bugprone
} // namespace tidy
} // namespace clang
#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_BUGPRONE_INCORRECTROUNDINGSCHECK_H_