[clang] [clang-tools-extra] [clang-tidy] New performance linter: performance-inefficient-copy-assign (PR #179467)

[via cfe-commits]

github-actions[bot] wrote:

<!--LLVM CODE LINT COMMENT: clang-tidy-->


:warning: C/C++ code linter, clang-tidy found issues in your code. :warning:

<details>
<summary>
You can test this locally with the following command:
</summary>

```bash

git diff -U0 origin/main...HEAD -- clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.cpp clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.h clang-tools-extra/clang-tidy/performance/PerformanceTidyModule.cpp |
python3 clang-tools-extra/clang-tidy/tool/clang-tidy-diff.py   -path build -p1 -quiet
```

</details>

<details>
<summary>
View the output from clang-tidy here.
</summary>

```
clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.cpp:18:1: warning: included header SmallPtrSet.h is not used directly [misc-include-cleaner]
   18 | #include "llvm/ADT/SmallPtrSet.h"
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   19 | 
clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.cpp:20:1: warning: included header ExprSequence.h is not used directly [misc-include-cleaner]
   20 | #include "../utils/ExprSequence.h"
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   21 | #include "../utils/Matchers.h"
clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.cpp:21:1: warning: included header Matchers.h is not used directly [misc-include-cleaner]
   21 | #include "../utils/Matchers.h"
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   22 | #include <optional>
clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.cpp:22:1: warning: included header optional is not used directly [misc-include-cleaner]
   22 | #include <optional>
      | ^~~~~~~~~~~~~~~~~~~
   23 | 
clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.cpp:47:5: warning: variable 'Options' of type 'CFG::BuildOptions' can be declared 'const' [misc-const-correctness]
   47 |     CFG::BuildOptions Options;
      |     ^
      |                       const 
clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.cpp:67:3: warning: variable 'AssignValueQual' of type 'QualType' can be declared 'const' [misc-const-correctness]
   67 |   QualType AssignValueQual = AssignValueDecl->getType();
      |   ^
      |            const 

clang-tools-extra/clang-tidy/performance/InefficientCopyAssignCheck.h:10:9: warning: header guard does not follow preferred style [llvm-header-guard]
   10 | #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_INEFFICIENTCOPYASSIGN_H
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |         LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_INEFFICIENTCOPYASSIGNCHECK_H
   11 | #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_INEFFICIENTCOPYASSIGN_H
      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      |         LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_INEFFICIENTCOPYASSIGNCHECK_H
```

</details>


https://github.com/llvm/llvm-project/pull/179467