Merge branch 'release/0.18'

crystal-lang · Jun 21, 2016 · e0f83fd · e0f83fd
2 parents 8a602d7 + 4c52d48
commit e0f83fd
Showing 2 changed files with 26 additions and 3 deletions.
diff --git a/spec/compiler/codegen/struct_spec.cr b/spec/compiler/codegen/struct_spec.cr
@@ -606,4 +606,23 @@ describe "Code gen: struct" do
        x.as(Bar).foo
        )).to_i.should eq(1)
   end
+
+  it "casts virtual struct to base type, only one subclass (#2885)" do
+    run(%(
+      abstract struct Entry
+        def initialize(@uid : String, @country : String)
+        end
+
+        def uid
+          @uid
+        end
+      end
+
+      struct MyEntry < Entry
+      end
+
+      entry = MyEntry.new("1", "GER")
+      entry.as(Entry).uid
+      )).to_string.should eq("1")
+  end
 end
diff --git a/src/compiler/crystal/codegen/codegen.cr b/src/compiler/crystal/codegen/codegen.cr
@@ -1956,9 +1956,13 @@ module Crystal
 
       if type.is_a?(VirtualType)
         if type.struct?
-          # For a struct we need to cast the second part of the union to the base type
-          value_ptr = gep(pointer, 0, 1)
-          pointer = bit_cast value_ptr, llvm_type(type.base_type).pointer
+          if type.remove_indirection.is_a?(UnionType)
+            # For a struct we need to cast the second part of the union to the base type
+            value_ptr = gep(pointer, 0, 1)
+            pointer = bit_cast value_ptr, llvm_type(type.base_type).pointer
+          else
+            # Nothing, there's only one subclass so it's the struct already
+          end
         else
           pointer = cast_to pointer, type.base_type
         end