[clang] [clang-tools-extra] [clang-tidy][dataflow] Add `bugprone-null-check-after-dereference` check (PR #84166)

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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/bugprone/NullCheckAfterDereferenceCheck.cpp clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.h clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.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/bugprone/NullCheckAfterDereferenceCheck.cpp:16:1: warning: #includes are not sorted properly [llvm-include-order]
note: this fix will not be applied because it overlaps with another fix
   16 | #include "clang/Analysis/FlowSensitive/DataflowAnalysisContext.h"
      | ^
clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp:18:1: warning: included header DataflowLattice.h is not used directly [misc-include-cleaner]
   18 | #include "clang/Analysis/FlowSensitive/DataflowLattice.h"
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   19 | #include "clang/Analysis/FlowSensitive/Models/NullPointerAnalysisModel.h"
clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp:22:1: warning: included header Any.h is not used directly [misc-include-cleaner]
   22 | #include "llvm/ADT/Any.h"
      | ^~~~~~~~~~~~~~~~~~~~~~~~~
   23 | #include "llvm/ADT/STLExtras.h"
clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp:27:1: warning: included header vector is not used directly [misc-include-cleaner]
   27 | #include <vector>
      | ^~~~~~~~~~~~~~~~~
   28 | 
clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp:38:8: warning: struct 'ExpandedResult' can be moved into an anonymous namespace to enforce internal linkage [misc-use-internal-linkage]
   38 | struct ExpandedResult {
      |        ^
clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp:64:3: warning: variable 'Env' of type 'dataflow::Environment' can be declared 'const' [misc-const-correctness]
   64 |   dataflow::Environment Env(AnalysisContext, FuncDecl);
      |   ^
      |                         const 
clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp:83:25: warning: 'auto Val' can be declared as 'const auto *Val' [llvm-qualified-auto]
   83 |                     if (auto Val = Diagnoser.WarningLocToVal[Entry.Location];
      |                         ^~~~
      |                         const auto *
clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp:84:25: warning: 'auto DerefExpr' can be declared as 'const auto *DerefExpr' [llvm-qualified-auto]
   84 |                         auto DerefExpr = Diagnoser.ValToDerefLoc[Val]) {
      |                         ^~~~
      |                         const auto *
clang-tools-extra/clang-tidy/bugprone/NullCheckAfterDereferenceCheck.cpp:97:8: warning: invalid case style for variable 'containsPointerValue' [readability-identifier-naming]
   97 |   auto containsPointerValue =
      |        ^~~~~~~~~~~~~~~~~~~~
      |        ContainsPointerValue
   98 |       hasDescendant(NullPointerAnalysisModel::ptrValueMatcher());
   99 |   Finder->addMatcher(
  100 |       decl(anyOf(functionDecl(unless(isExpansionInSystemHeader()),
  101 |                               // FIXME: Remove the filter below when lambdas are
  102 |                               // well supported by the check.
  103 |                               unless(hasDeclContext(cxxRecordDecl(isLambda()))),
  104 |                               hasBody(containsPointerValue)),
      |                                       ~~~~~~~~~~~~~~~~~~~~
      |                                       ContainsPointerValue
  105 |                  cxxConstructorDecl(
  106 |                      unless(hasDeclContext(cxxRecordDecl(isLambda()))),
  107 |                      hasAnyConstructorInitializer(
  108 |                          withInitializer(containsPointerValue)))))
      |                                          ~~~~~~~~~~~~~~~~~~~~
      |                                          ContainsPointerValue
```

</details>


https://github.com/llvm/llvm-project/pull/84166