tree 30940f14751903c3f4ed40beb4f240c2c46d6092
parent 0d4427d10d6971c36d165d77ba559d8ac059cea5
author Bruno Cardoso Lopes <bruno.cardoso@gmail.com> 1486628687 -0800
committer Bruno Cardoso Lopes <bruno.cardoso@gmail.com> 1486677094 -0800

Avoid VarDecl emission attempt if no owning module avaiable

This fixes PR31863, a regression introduced in r276159.

Consider this snippet:

struct FVector;
struct FVector {};
struct FBox {
  FVector Min;
  FBox(int);
};
namespace {
FBox InvalidBoundingBox(0);
}

While parsing the DECL_VAR for 'struct FBox', clang recursively read all the
dep decls until it finds the DECL_CXX_RECORD forward declaration for 'struct
FVector'. Then, it resumes all the way up back to DECL_VAR handling in
`ReadDeclRecord`, where it checks if `isConsumerInterestedIn` for the decl.

One of the condition for `isConsumerInterestedIn` to return false is if the
VarDecl is imported from a module `D->getImportedOwningModule()`, because it
will get emitted when we import the relevant module. However, before checking
if it comes from a module, clang checks if `Ctx.DeclMustBeEmitted(D)`, which
triggers the emission of 'struct FBox'. Since one of its fields is still
incomplete, it crashes.

Instead, check if `D->getImportedOwningModule()` is true before calling
`Ctx.DeclMustBeEmitted(D)`.

rdar://problem/30173654