Go patch committed: Build type descriptor for alias in other package

[Ian Lance Taylor]

This patch to the Go frontend by Cherry Zhang generates type
descriptors for pointers to aliases defined in other packages.  When a
type descriptor is needed (for e.g. interface conversion), if the type
is a pointer to a named type defined in another package, we don't
generate the definition of the type descriptor because it is generated
in the package where the type is defined.  However, if the named type
is an alias to an unnamed type, its descriptor is not generated in the
other package, and we need to generate it.  Bootstrapped and ran Go
testsuite on x86_64-pc-linux-gnu.  Committed to mainline.

Ian

Index: gcc/go/gofrontend/MERGE
===================================================================
--- gcc/go/gofrontend/MERGE     (revision 279136)
+++ gcc/go/gofrontend/MERGE     (working copy)
@@ -1,4 +1,4 @@
-6f2bf15e15bf7516c393966577d72b79cba7f980
+85641a0f26061f7c98db42a2adb3250c07ce504e
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
Index: gcc/go/gofrontend/types.cc
===================================================================
--- gcc/go/gofrontend/types.cc  (revision 278984)
+++ gcc/go/gofrontend/types.cc  (working copy)
@@ -1453,13 +1453,13 @@ Type::type_descriptor_defined_elsewhere(
   else
     {
       if (this->points_to() != NULL
-         && this->points_to()->named_type() != NULL
-         && this->points_to()->named_type()->named_object()->package() != NULL)
+         && this->points_to()->unalias()->named_type() != NULL
+         && 
this->points_to()->unalias()->named_type()->named_object()->package() != NULL)
        {
          // This is an unnamed pointer to a named type defined in a
          // different package.  The descriptor should be defined in
          // that package.
-         *package = this->points_to()->named_type()->named_object()->package();
+         *package = 
this->points_to()->unalias()->named_type()->named_object()->package();
          return true;
        }
     }