diff --git a/src/cmd/compile/internal/importer/iimport.go b/src/cmd/compile/internal/importer/iimport.go
index 523b00313d..99eb964415 100644
--- a/src/cmd/compile/internal/importer/iimport.go
+++ b/src/cmd/compile/internal/importer/iimport.go
@@ -364,10 +364,6 @@ func (r *importReader) obj(name string) {
 		if r.p.exportVersion < iexportVersionGenerics {
 			errorf("unexpected type param type")
 		}
-		// Type parameter indices are lazily "allocated".
-		// There's no need to export them anymore.
-		// TODO change the export format accordingly
-		_ = int(r.int64())
 		name0, sub := parseSubscript(name)
 		tn := types2.NewTypeName(pos, r.currPkg, name0, nil)
 		t := (*types2.Checker)(nil).NewTypeParam(tn, nil)
diff --git a/src/cmd/compile/internal/typecheck/iexport.go b/src/cmd/compile/internal/typecheck/iexport.go
index d877b03e48..2944908bcb 100644
--- a/src/cmd/compile/internal/typecheck/iexport.go
+++ b/src/cmd/compile/internal/typecheck/iexport.go
@@ -531,7 +531,6 @@ func (p *iexporter) doDecl(n *ir.Name) {
 			// A typeparam has a name, and has a type bound rather
 			// than an underlying type.
 			w.pos(n.Pos())
-			w.int64(int64(n.Type().Index()))
 			w.typ(n.Type().Bound())
 			break
 		}
diff --git a/src/cmd/compile/internal/typecheck/iimport.go b/src/cmd/compile/internal/typecheck/iimport.go
index 2957212fb2..2e8b18c0b7 100644
--- a/src/cmd/compile/internal/typecheck/iimport.go
+++ b/src/cmd/compile/internal/typecheck/iimport.go
@@ -388,8 +388,9 @@ func (r *importReader) doDecl(sym *types.Sym) *ir.Name {
 			// this types2-to-types1 translation.
 			return sym.Def.(*ir.Name)
 		}
-		index := int(r.int64())
-		t := types.NewTypeParam(sym, index)
+		// The typeparam index is set at the point where the containing type
+		// param list is imported.
+		t := types.NewTypeParam(sym, 0)
 		// Nname needed to save the pos.
 		nname := ir.NewDeclNameAt(pos, ir.OTYPE, sym)
 		sym.Def = nname
@@ -875,6 +876,9 @@ func (r *importReader) typeList() []*types.Type {
 	ts := make([]*types.Type, n)
 	for i := range ts {
 		ts[i] = r.typ()
+		if ts[i].IsTypeParam() {
+			ts[i].SetIndex(i)
+		}
 	}
 	return ts
 }
@@ -887,6 +891,7 @@ func (r *importReader) tparamList() []*types.Field {
 	fs := make([]*types.Field, n)
 	for i := range fs {
 		typ := r.typ()
+		typ.SetIndex(i)
 		fs[i] = types.NewField(typ.Pos(), typ.Sym(), typ)
 	}
 	return fs
diff --git a/src/cmd/compile/internal/types/type.go b/src/cmd/compile/internal/types/type.go
index 1f01498ca1..099080f48f 100644
--- a/src/cmd/compile/internal/types/type.go
+++ b/src/cmd/compile/internal/types/type.go
@@ -1885,6 +1885,12 @@ func (t *Type) Index() int {
 	return t.Extra.(*Typeparam).index
 }
 
+// SetIndex sets the index of the type param within its param list.
+func (t *Type) SetIndex(i int) {
+	t.wantEtype(TTYPEPARAM)
+	t.Extra.(*Typeparam).index = i
+}
+
 // SetBound sets the bound of a typeparam.
 func (t *Type) SetBound(bound *Type) {
 	t.wantEtype(TTYPEPARAM)