[openmp] [clang-tools-extra] [llvm] [clang-tidy] Add bugprone-move-shared-pointer-contents check. (PR #67467)

[Piotr Zegar via llvm-commits]

================
@@ -0,0 +1,51 @@
+//===--- MoveSharedPointerContentsCheck.cpp - clang-tidy ------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "MoveSharedPointerContentsCheck.h"
+#include "../ClangTidyCheck.h"
+#include "../utils/Matchers.h"
+#include "../utils/OptionsUtils.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+
+using namespace clang::ast_matchers;
+
+namespace clang::tidy::bugprone {
+
+MoveSharedPointerContentsCheck::MoveSharedPointerContentsCheck(
+    StringRef Name, ClangTidyContext *Context)
+    : ClangTidyCheck(Name, Context),
+      SharedPointerClasses(utils::options::parseStringList(
+          Options.get("SharedPointerClasses", "std::shared_ptr"))) {}
+
+void MoveSharedPointerContentsCheck::registerMatchers(MatchFinder *Finder) {
+  Finder->addMatcher(
+      callExpr(
+          callee(functionDecl(hasName("std::move"))),
+          hasArgument(0, cxxOperatorCallExpr(hasOverloadedOperatorName("*"),
+                                             callee(cxxMethodDecl(ofClass(
+                                                 matchers::matchesAnyListedName(
+                                                     SharedPointerClasses)))))
+                             .bind("op")))
+          .bind("call"),
+      this);
+}
+
+void MoveSharedPointerContentsCheck::check(
+    const MatchFinder::MatchResult &Result) {
+  const auto *Call = Result.Nodes.getNodeAs<CallExpr>("call");
+  const auto *Op = Result.Nodes.getNodeAs<Expr>("op");
+
+  diag(Call->getBeginLoc(),
+       "don't move the contents out of a shared pointer, as other accessors "
+       "expect them to remain in a determinate state")
+      << FixItHint::CreateInsertion(Call->getBeginLoc(), "*")
----------------
PiotrZSL wrote:

Remove fix, this isn't a valid one. Example:

```
#include <memory>

struct A{};

void test(A&&);

void w()
{
    std::shared_ptr<A> a;
    test(*std::move(a));
} 
```

this won't compile, operator * will return lvalue reference anyway.

https://github.com/llvm/llvm-project/pull/67467