diff --git a/core/codegen/declarations.go b/core/codegen/declarations.go
index 7eec291..16bdaea 100644
--- a/core/codegen/declarations.go
+++ b/core/codegen/declarations.go
@@ -2,6 +2,7 @@ package codegen
 
 import (
 	"fireball/core/ast"
+	"fireball/core/cst"
 	"fireball/core/ir"
 	"fireball/core/scanner"
 )
@@ -40,9 +41,9 @@ func (c *codegen) VisitFunc(decl *ast.Func) {
 	// Add this variable
 	if struct_ := decl.Method(); struct_ != nil {
 		name := scanner.Token{Kind: scanner.Identifier, Lexeme: "this"}
-		type_ := ast.Pointer{Pointee: struct_}
+		node := cst.Node{Kind: cst.IdentifierNode, Token: name, Range: decl.Name.Cst().Range}
 
-		c.scopes.addVariable(&ast.Token{Token_: name}, &type_, exprValue{v: function.Typ.Params[0]}, 1)
+		c.scopes.addVariable(ast.NewToken(node, name), struct_, exprValue{v: function.Typ.Params[0]}, 1)
 	}
 
 	// Copy parameters
diff --git a/core/codegen/expressions.go b/core/codegen/expressions.go
index 5e50637..a9c89f2 100644
--- a/core/codegen/expressions.go
+++ b/core/codegen/expressions.go
@@ -635,7 +635,7 @@ func (c *codegen) VisitCall(expr *ast.Call) {
 
 	for i, arg := range expr.Args {
 		if hasThis {
-			args[i+1] = c.loadExpr(arg).v
+			args[i+1] = c.implicitCastLoadExpr(function.Params[i].Type, arg).v
 		} else if i >= len(function.Params) {
 			args[i] = c.loadExpr(arg).v
 		} else {
@@ -657,7 +657,7 @@ func (c *codegen) VisitCall(expr *ast.Call) {
 		Args:   args,
 	})
 
-	c.setLocationMeta(result, expr)
+	c.setLocationMetaCst(result, expr, scanner.LeftParen)
 	c.exprResult = exprValue{v: result}
 
 	// If the function returns a constant-sized array and the array is immediately indexed then store it in an alloca first
@@ -696,7 +696,7 @@ func (c *codegen) VisitIndex(expr *ast.Index) {
 		Inbounds:   true,
 	})
 
-	c.setLocationMeta(result, expr)
+	c.setLocationMetaCst(result, expr, scanner.LeftBracket)
 
 	c.exprResult = exprValue{
 		v:           result,
@@ -739,7 +739,7 @@ func (c *codegen) VisitMember(expr *ast.Member) {
 						Inbounds: true,
 					})
 
-					c.setLocationMeta(result, expr)
+					c.setLocationMeta(result, expr.Name)
 
 					c.exprResult = exprValue{
 						v:           result,
@@ -751,7 +751,7 @@ func (c *codegen) VisitMember(expr *ast.Member) {
 						Indices: []uint32{uint32(node.Index())},
 					})
 
-					c.setLocationMeta(result, expr)
+					c.setLocationMeta(result, expr.Name)
 					c.exprResult = exprValue{v: result}
 				}
 			}
diff --git a/core/codegen/instructions.go b/core/codegen/instructions.go
index be85ad5..b965b53 100644
--- a/core/codegen/instructions.go
+++ b/core/codegen/instructions.go
@@ -3,6 +3,7 @@ package codegen
 import (
 	"fireball/core/ast"
 	"fireball/core/ir"
+	"fireball/core/scanner"
 )
 
 func (c *codegen) alloca(type_ ast.Type, name string, node ast.Node) ir.Value {
@@ -40,3 +41,22 @@ func (c *codegen) setLocationMeta(value ir.MetaValue, node ast.Node) {
 
 	value.SetMeta(c.module.Meta(meta))
 }
+
+func (c *codegen) setLocationMetaCst(value ir.MetaValue, node ast.Node, kind scanner.TokenKind) {
+	if node == nil {
+		return
+	}
+
+	meta := &ir.LocationMeta{
+		Scope: c.scopes.getMeta(),
+	}
+
+	if node.Cst() != nil {
+		token := node.Cst().Get(kind)
+
+		meta.Line = uint32(token.Range.Start.Line)
+		meta.Column = uint32(token.Range.Start.Column)
+	}
+
+	value.SetMeta(c.module.Meta(meta))
+}
diff --git a/core/codegen/types.go b/core/codegen/types.go
index cb17d9f..1c6fd4b 100644
--- a/core/codegen/types.go
+++ b/core/codegen/types.go
@@ -269,11 +269,13 @@ func (t *types) getMeta(type_ ast.Type) ir.MetaID {
 				Elements: []ir.MetaID{
 					t.module.Meta(&ir.DerivedTypeMeta{
 						Tag:      ir.MemberTag,
+						Name:     "vtable",
 						BaseType: t.getMeta(&ptr),
 						Offset:   0,
 					}),
 					t.module.Meta(&ir.DerivedTypeMeta{
 						Tag:      ir.MemberTag,
+						Name:     "data",
 						BaseType: t.getMeta(&ptr),
 						Offset:   ptr.Size() * 8,
 					}),
@@ -380,6 +382,7 @@ func (t *types) getMeta(type_ ast.Type) ir.MetaID {
 
 			fields[i] = t.module.Meta(&ir.DerivedTypeMeta{
 				Tag:      ir.MemberTag,
+				Name:     field.Name.String(),
 				BaseType: t.getMeta(field.Type),
 				Offset:   offset * 8,
 			})
diff --git a/core/ir/metadata.go b/core/ir/metadata.go
index 0c80ab9..c178afd 100644
--- a/core/ir/metadata.go
+++ b/core/ir/metadata.go
@@ -261,6 +261,7 @@ type DerivedTypeMeta struct {
 	baseMeta
 
 	Tag      DerivedTagKind
+	Name     string
 	BaseType MetaID
 
 	Size  uint32
diff --git a/core/llvm/metadata.go b/core/llvm/metadata.go
index 471dc80..7ca8d8b 100644
--- a/core/llvm/metadata.go
+++ b/core/llvm/metadata.go
@@ -144,6 +144,11 @@ func (w *textWriter) writeMeta(meta ir.Meta) {
 		w.writeString("tag: ")
 		w.writeString(meta.Tag.String())
 
+		if meta.Name != "" {
+			w.writeString(", name: ")
+			w.writeQuotedString(meta.Name)
+		}
+
 		w.writeString(", baseType: ")
 		w.writeMetaRef(meta.BaseType)
 
@@ -340,7 +345,7 @@ func (w *textWriter) writeMeta(meta ir.Meta) {
 		w.writeUint(uint64(meta.Line), 10)
 
 		w.writeString(", column: ")
-		w.writeUint(uint64(meta.Column), 10)
+		w.writeUint(uint64(meta.Column)+1, 10)
 
 		w.writeRune(')')