[PATCH] D126780: [clang-tidy] `bugprone-use-after-move`: Fix handling of moves in lambda captures

[Martin Böhme via Phabricator via cfe-commits]

mboehme created this revision.
Herald added subscribers: carlosgalvezp, xazax.hun.
Herald added a project: All.
mboehme requested review of this revision.
Herald added a project: clang-tools-extra.
Herald added a subscriber: cfe-commits.

Previously, we were treating a move in the lambda capture as if it happened
within the body of the lambda, not within the function that defines the lambda.

This fixes the same bug as https://reviews.llvm.org/D119165 (which it appears
may have been abandoned by the author?) but does so more simply.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D126780

Files:
  clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp
  clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp


Index: clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp
===================================================================
--- clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp
+++ clang-tools-extra/test/clang-tidy/checkers/bugprone-use-after-move.cpp
@@ -416,6 +416,13 @@
     auto lambda = [&]() { a.foo(); };
     std::move(a);
   }
+  {
+    A a;
+    auto lambda = [a = std::move(a)] { a.foo(); };
+    a.foo();
+    // CHECK-NOTES: [[@LINE-1]]:5: warning: 'a' used after it was moved
+    // CHECK-NOTES: [[@LINE-3]]:24: note: move occurred here
+  }
 }
 
 // Use-after-moves are detected in uninstantiated templates if the moved type
Index: clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp
===================================================================
--- clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp
+++ clang-tools-extra/clang-tidy/bugprone/UseAfterMoveCheck.cpp
@@ -400,7 +400,8 @@
   auto CallMoveMatcher =
       callExpr(callee(functionDecl(hasName("::std::move"))), argumentCountIs(1),
                hasArgument(0, declRefExpr().bind("arg")),
-               anyOf(hasAncestor(lambdaExpr().bind("containing-lambda")),
+               anyOf(hasAncestor(compoundStmt(
+                         hasParent(lambdaExpr().bind("containing-lambda")))),
                      hasAncestor(functionDecl().bind("containing-func"))),
                unless(inDecltypeOrTemplateArg()),
                // try_emplace is a common maybe-moving function that returns a


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