-Wdangling-field detects view members initalized from a by-value owner parameter

描述

struct Foo {};
struct Bar {
  const Foo& foo;
  Bar(Foo f ) : foo(f) {} // good, clang warn on this case
};


struct C {
    string_view s;
    C(std::string c) : s(c) {} // bad, clang doesn't warn on this case. support it
};

貢獻者指南

技術棧

cpp

領域

toolingdeveloper experience

議題類型

feature

難度面向新貢獻者的預計實作難度，1 表示很小改動，5 表示專家級工作。

4

預計時間有經驗貢獻者完成調查、實作、測試並準備 pull request 的粗略時間範圍。

3-5 days

活動狀態議題目前的可參與程度：新鮮、活躍、陳舊、阻塞或等待維護者輸入。

fresh

清晰度議題是否清楚說明預期改動、驗收標準和下一步。

clear

前置要求

C++LLVM/clang development environment setup

新手友善度1-100 的估計分數，表示該議題對首次貢獻者的友善程度。

25

研究方向

Investigate how clang's Wdangling field warning currently detects member initialization from temporary owners. The relevant code is likely in clang/lib/Sema/SemaChecking.cpp or similar diagnostic implementation. Extending the warning to cover std::string view and similar view types when initialized from a by value parameter requires adding logic to recognize view types (e.g., std::string view, std::span) that hold references to temporary strings. Look at existing patterns for detecting dangling references and consider adding a new check for view member init from by value std::string parameters. Review comments on the issue for any suggested approach.