1 files changed, 27 insertions, 7 deletions

diff --git a/libgo/go/debug/dwarf/type.go b/libgo/go/debug/dwarf/type.go
index a5daa1d0bb1..c76a472d78c 100644
--- a/libgo/go/debug/dwarf/type.go
+++ b/libgo/go/debug/dwarf/type.go
@@ -275,12 +275,14 @@ type typeReader interface {
 
 // Type reads the type at off in the DWARF ``info'' section.
 func (d *Data) Type(off Offset) (Type, error) {
-	return d.readType("info", d.Reader(), off, d.typeCache)
+	return d.readType("info", d.Reader(), off, d.typeCache, nil)
 }
 
-// readType reads a type from r at off of name using and updating a
-// type cache.
-func (d *Data) readType(name string, r typeReader, off Offset, typeCache map[Offset]Type) (Type, error) {
+// readType reads a type from r at off of name. It adds types to the
+// type cache, appends new typedef types to typedefs, and computes the
+// sizes of types. Callers should pass nil for typedefs; this is used
+// for internal recursion.
+func (d *Data) readType(name string, r typeReader, off Offset, typeCache map[Offset]Type, typedefs *[]*TypedefType) (Type, error) {
 	if t, ok := typeCache[off]; ok {
 		return t, nil
 	}
@@ -294,9 +296,24 @@ func (d *Data) readType(name string, r typeReader, off Offset, typeCache map[Off
 		return nil, DecodeError{name, off, "no type at offset"}
 	}
 
+	// If this is the root of the recursion, prepare to resolve
+	// typedef sizes once the recursion is done. This must be done
+	// after the type graph is constructed because it may need to
+	// resolve cycles in a different order than readType
+	// encounters them.
+	if typedefs == nil {
+		var typedefList []*TypedefType
+		defer func() {
+			for _, t := range typedefList {
+				t.Common().ByteSize = t.Type.Size()
+			}
+		}()
+		typedefs = &typedefList
+	}
+
 	// Parse type from Entry.
 	// Must always set typeCache[off] before calling
-	// d.Type recursively, to handle circular types correctly.
+	// d.readType recursively, to handle circular types correctly.
 	var typ Type
 
 	nextDepth := 0
@@ -345,7 +362,7 @@ func (d *Data) readType(name string, r typeReader, off Offset, typeCache map[Off
 		var t Type
 		switch toff := tval.(type) {
 		case Offset:
-			if t, err = d.readType(name, r.clone(), toff, typeCache); err != nil {
+			if t, err = d.readType(name, r.clone(), toff, typeCache, typedefs); err != nil {
 				return nil
 			}
 		case uint64:
@@ -674,7 +691,10 @@ func (d *Data) readType(name string, r typeReader, off Offset, typeCache map[Off
 			b = -1
 			switch t := typ.(type) {
 			case *TypedefType:
-				b = t.Type.Size()
+				// Record that we need to resolve this
+				// type's size once the type graph is
+				// constructed.
+				*typedefs = append(*typedefs, t)
 			case *PtrType:
 				b = int64(addressSize)
 			}