[PATCH] D135025: [clang][Interp] Support base class constructors

[Aaron Ballman via Phabricator via cfe-commits]

aaron.ballman added inline comments.


================
Comment at: clang/lib/AST/Interp/ByteCodeExprGen.h:258
+  /// or nullptr if no such decl exists.
+  const CXXRecordDecl * getRecordDecl(const Expr *E) const {
+    QualType T = E->getType();
----------------



================
Comment at: clang/test/AST/Interp/records.cpp:209
+  static_assert(d.getA() == 20);
+  static_assert(d.getB() == 30);
+};
----------------
I'd appreciate some more failure test cases, if they're not already covered elsewhere:
```
struct Base {
  int Val;
};

struct Derived : Base {
  int OtherVal;

  constexpr Derived(int i) : OtherVal(i) {}
};

// Something here should be diagnosed; either because the Derived ctor is not a
// valid constexpr function or because we're accessing an uninitialized member.
constexpr Derived D(12);
static_assert(D.Val == 0);


// Another test is when a constexpr ctor calls a non-constexpr base class ctor.
struct AnotherBase {
  int Val;
  constexpr AnotherBase(int i) : Val(12 / i) {}
};

struct AnotherDerived : AnotherBase {
  constexpr AnotherDerived(int i) : AnotherBase(i) {}
};
constexpr AnotherDerived Derp(0);

// Skipping the derived class constructor is also
// interesting to consider:
struct YetAnotherBase {
  int Val;
  constexpr YetAnotherBase(int i) : Val(i) {}
};

struct YetAnotherDerived : YetAnotherBase {
  using YetAnotherBase::YetAnotherBase;
  
  int OtherVal;

  constexpr bool doit() const { return Val == OtherVal; }
};

constexpr YetAnotherDerived Oops(0);
```


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D135025/new/

https://reviews.llvm.org/D135025