From c3d517e17ff19f1cb451345d12dc3ebcd84d89e6 Mon Sep 17 00:00:00 2001
From: David Nadlinger <code@klickverbot.at>
Date: Fri, 4 Jan 2013 07:26:15 +0100
Subject: [PATCH] Correctly handle ref variables in an outer frame.

Fixes DMD testcase 'testcontracts'.
---
 gen/dvalue.cpp | 7 +++++++
 gen/dvalue.h   | 4 ++++
 gen/toir.cpp   | 8 +++-----
 3 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/gen/dvalue.cpp b/gen/dvalue.cpp
index 05ef76af5a..9da1644838 100644
--- a/gen/dvalue.cpp
+++ b/gen/dvalue.cpp
@@ -57,6 +57,13 @@ LLValue* DVarValue::getRVal()
     return DtoLoad(tmp);
 }
 
+LLValue* DVarValue::getRefStorage()
+{
+    assert(val);
+    assert(isSpecialRefVar(var));
+    return val;
+}
+
 /////////////////////////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////////////////////////
 
diff --git a/gen/dvalue.h b/gen/dvalue.h
index fa1982e2cf..1e91bc82b8 100644
--- a/gen/dvalue.h
+++ b/gen/dvalue.h
@@ -110,6 +110,10 @@ struct DVarValue : DValue
     virtual llvm::Value* getLVal();
     virtual llvm::Value* getRVal();
 
+    /// Returns the underlying storage for special internal ref variables.
+    /// Illegal to call on any other value.
+    virtual llvm::Value* getRefStorage();
+
     virtual DVarValue* isVar() { return this; }
 };
 
diff --git a/gen/toir.cpp b/gen/toir.cpp
index 38918a3f50..cfdcb306c7 100644
--- a/gen/toir.cpp
+++ b/gen/toir.cpp
@@ -597,12 +597,10 @@ DValue* AssignExp::toElem(IRState* p)
                 // Note that the variable value is accessed directly (instead
                 // of via getLValue(), which would perform a load from the
                 // uninitialized location), and that rhs is stored as an l-value!
-
-                IrLocal* const local = ve->var->ir.irLocal;
-                assert(local && "ref var must be local and already initialized");
-
+                DVarValue* lhs = e1->toElem(p)->isVar();
+                assert(lhs);
                 DValue* rhs = e2->toElem(p);
-                DtoStore(rhs->getLVal(), local->value);
+                DtoStore(rhs->getLVal(), lhs->getRefStorage());
                 return rhs;
             }
         }