name lookup from lazily deserializing the other declarations with the same
name, by tracking a bit to indicate whether a name in a DeclContext might have
additional external results. This also allows lazier reconciling of the lookup
table if a module import adds decls to a pre-existing DC.
However, this exposes a pre-existing bug, which causes a regression in
test/Modules/decldef.mm: if we have a reference to a declaration, and a
later-imported module adds a redeclaration, nothing causes us to load that
redeclaration when we use or emit the reference (which can manifest as a
reference to an undefined inline function, a use of an incomplete type, and so
on). decldef.mm has been extended with an additional testcase which fails with
or without this change.
llvm-svn: 190293
visible.
The basic problem here is that a given translation unit can use
forward declarations to form pointers to a given type, say,
class X;
X *x;
and then import a module that includes a definition of X:
import XDef;
We will then fail when attempting to access a member of X, e.g.,
x->method()
because the AST reader did not know to look for a default of a class
named X within the new module.
This implementation is a bit of a C-centric hack, because the only
definitions that can have this property are enums, structs, unions,
Objective-C classes, and Objective-C protocols, and all of those are
either visible at the top-level or can't be defined later. Hence, we
can use the out-of-date-ness of the name and the identifier-update
mechanism to force the update.
In C++, we will not be so lucky, and will need a more advanced
solution, because the definitions could be in namespaces defined in
two different modules, e.g.,
// module 1
namespace N { struct X; }
// module 2
namespace N { struct X { /* ... */ }; }
One possible implementation here is for C++ to extend the information
associated with each identifier table to include the declaration IDs
of any definitions associated with that name, regardless of
context. We would have to eagerly load those definitions.
llvm-svn: 174794
include stack to find the first file that is known to be part of the
module. This copes with situations where the module map doesn't
completely specify all of the headers that are involved in the module,
which can come up when there are very strange #include_next chains
(e.g., with weird compiler/stdlib headers like stdarg.h or float.h).
llvm-svn: 147662
Richard Smith