```cpp
struct Base {
int m;
};
template <class T>
struct Derived : Base {
Derived() { m = 0; }
};
```
would previously generate the following output:
```
<source>:7:15: warning: 'm' should be initialized in a member initializer of the constructor [cppcoreguidelines-prefer-member-initializer]
7 | Derived() { m = 0; }
| ^~~~~~
| : m(0)
```
This patch fixes this false positive.
Note that before this patch the checker won't give false positive for
```cpp
struct Derived : Base {
Derived() { m = 0; }
};
```
and the constructor's AST is
```
`-CXXConstructorDecl 0x557df03d1fb0 <line:7:3, col:22> col:3 Derived 'void ()' implicit-inline
|-CXXCtorInitializer 'Base'
| `-CXXConstructExpr 0x557df03d2748 <col:3> 'Base' 'void () noexcept'
`-CompoundStmt 0x557df03d2898 <col:13, col:22>
`-BinaryOperator 0x557df03d2878 <col:15, col:19> 'int' lvalue '='
|-MemberExpr 0x557df03d2828 <col:15> 'int' lvalue ->m 0x557df03d1c40
| `-ImplicitCastExpr 0x557df03d2808 <col:15> 'Base *' <UncheckedDerivedToBase (Base)>
| `-CXXThisExpr 0x557df03d27f8 <col:15> 'Derived *' implicit this
`-IntegerLiteral 0x557df03d2858 <col:19> 'int' 0
```
so `isAssignmentToMemberOf` would return empty due to
f0967fca04/clang-tools-extra/clang-tidy/cppcoreguidelines/PreferMemberInitializerCheck.cpp (L118-L119)Fixes#104400
326d749a36