[PATCH] D139741: [clang][CodeGen] Use base subobject type layout for potentially-overlapping fields

[Jordan Rupprecht via Phabricator via cfe-commits]

rupprecht added a comment.

In D139741#4000201 <https://reviews.llvm.org/D139741#4000201>, @rupprecht wrote:

> I'm not sure what the libcxx failure was that caused you to revert this, but we also saw a clang crasher as a result of this. `clang/lib/AST/Decl.cpp:4300 in unsigned int clang::FieldDecl::getBitWidthValue(const ASTContext &) const: isBitField() && "not a bitfield"`. I'll try to reduce it.

Here:

  template <class F, class X, class Y>
  struct Foo {
    Foo(F, X, Y y) : y_(y) {}
    Y y_;
    union FooHolder {
      int foo;
    };
    [[no_unique_address]] FooHolder foo_holder_;
  };
  template <typename Factory, typename X, typename Y>
  void MakeFoo(Factory f, X x, Y y) {
    Foo(f, x, y);
  }
  void Start() {
    MakeFoo(0, int(), [] {});
  }


Repository:
  rG LLVM Github Monorepo

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