Partial fix for #69 — LDC1 from master fails to build Tango.

Fixed regression that has been introduced in commit 9889067.

gen/functions.cpp

@@ -87,11 +87,7 @@ llvm::FunctionType* DtoFunctionType(Type* type, Type* thistype, Type* nesttype,
     // member functions
     if (thistype)
     {
-        bool toref = (thistype->toBasetype()->ty == Tstruct);
-#if STRUCTTHISREF
-        fty.is_arg_this_ref = toref;
-#endif
-        fty.arg_this = new IrFuncTyArg(thistype, toref);
+        fty.arg_this = new IrFuncTyArg(thistype, thistype->toBasetype()->ty == Tstruct);
         lidx++;
     }
 
@@ -712,7 +708,10 @@ void DtoDefineFunction(FuncDeclaration* fd)
         assert(thisvar);
 
         LLValue* thismem = thisvar;
-        if (!f->fty.is_arg_this_ref) {
+    #if STRUCTTHISREF
+        if (!f->fty.arg_this->byref)
+    #endif
+        {
             thismem = DtoRawAlloca(thisvar->getType(), 0, "this"); // FIXME: align?
             DtoStore(thisvar, thismem);
             irfunction->thisArg = thismem;
@@ -722,6 +721,7 @@ void DtoDefineFunction(FuncDeclaration* fd)
         fd->vthis->ir.irParam = new IrParameter(fd->vthis);
         fd->vthis->ir.irParam->value = thismem;
         fd->vthis->ir.irParam->arg = f->fty.arg_this;
+        fd->vthis->ir.irParam->isVthis = true;
 
         DtoDwarfLocalVariable(thismem, fd->vthis);
 

gen/nested.cpp

@@ -463,12 +463,19 @@ static void DtoCreateNestedContextType(FuncDeclaration* fd) {
                 if (vd->isParameter()) {
                     // Parameters will have storage associated with them (to handle byref etc.),
                     // so handle those cases specially by storing a pointer instead of a value.
-                    assert(vd->ir.irParam->value);
-                    LLValue* value = vd->ir.irParam->value;
+                    IrParameter * irparam = vd->ir.irParam;
+                    LLValue* value = irparam->value;
+                    assert(value);
                     LLType* type = value->getType();
                     bool refout = vd->storage_class & (STCref | STCout);
                     bool lazy = vd->storage_class & STClazy;
-                    if (!refout && (!vd->ir.irParam->arg->byref || lazy)) {
+                    bool byref = irparam->arg->byref;
+                #if STRUCTTHISREF
+                    bool isVthisPtr = irparam->isVthis && !byref;
+                #else
+                    bool isVthisPtr = irparam->isVthis;
+                #endif
+                    if ((!refout && (!byref || lazy)) || isVthisPtr) {
                         // This will be copied to the nesting frame.
                         if (lazy)
                             type = type->getContainedType(0);

ir/irfuncty.h

@@ -79,9 +79,6 @@ struct IrFuncTy : IrBase
     // range of normal parameters to reverse
     bool reverseParams;
 
-    // arg_this is reference
-    bool is_arg_this_ref;
-
     IrFuncTy()
     :   ret(NULL),
 	    args(),
@@ -91,8 +88,7 @@ struct IrFuncTy : IrBase
         arg_arguments(NULL),
         arg_argptr(NULL),
         c_vararg(false),
-        reverseParams(false),
-        is_arg_this_ref(false)
+        reverseParams(false)
     {}
 
 #if defined(_MSC_VER)
@@ -107,8 +103,7 @@ struct IrFuncTy : IrBase
         arg_arguments(rhs.arg_arguments),
         arg_argptr(rhs.arg_argptr),
         c_vararg(rhs.c_vararg),
-        reverseParams(rhs.reverseParams),
-        is_arg_this_ref(rhs.is_arg_this_ref)
+        reverseParams(rhs.reverseParams)
     {}
 
     IrFuncTy& operator=(const IrFuncTy& rhs)
@@ -122,7 +117,6 @@ struct IrFuncTy : IrBase
         arg_argptr = rhs.arg_argptr;
         c_vararg = rhs.c_vararg;
         reverseParams = rhs.reverseParams;
-        is_arg_this_ref = rhs.is_arg_this_ref;
         return *this;
     }
 #endif

ir/irvar.cpp

@@ -38,7 +38,7 @@ IrLocal::IrLocal(VarDeclaration* v) : IrVar(v)
 //////////////////////////////////////////////////////////////////////////////
 //////////////////////////////////////////////////////////////////////////////
 
-IrParameter::IrParameter(VarDeclaration* v) : IrLocal(v), arg(0)
+IrParameter::IrParameter(VarDeclaration* v) : IrLocal(v), arg(0), isVthis(false)
 {
 }
 

ir/irvar.h

@@ -38,6 +38,7 @@ struct IrParameter : IrLocal
 {
     IrParameter(VarDeclaration* v);
     IrFuncTyArg *arg;
+    bool isVthis; // true, if it is the 'this' parameter
 };
 
 // represents an aggregate field variable