diff options
Diffstat (limited to 'src/cmd/compile/internal/types2/subst.go')
| -rw-r--r-- | src/cmd/compile/internal/types2/subst.go | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/src/cmd/compile/internal/types2/subst.go b/src/cmd/compile/internal/types2/subst.go index 26796fc604..044544f1f9 100644 --- a/src/cmd/compile/internal/types2/subst.go +++ b/src/cmd/compile/internal/types2/subst.go @@ -51,7 +51,9 @@ func (m *substMap) lookup(tpar *TypeParam) Type { // subst is functional in the sense that it doesn't modify the incoming // type. If a substitution took place, the result type is different from // from the incoming type. -func (check *Checker) subst(pos syntax.Pos, typ Type, smap *substMap) Type { +// +// If the given typMap is nil and check is non-nil, check.typMap is used. +func (check *Checker) subst(pos syntax.Pos, typ Type, smap *substMap, typMap map[string]*Named) Type { if smap.empty() { return typ } @@ -68,16 +70,21 @@ func (check *Checker) subst(pos syntax.Pos, typ Type, smap *substMap) Type { var subst subster subst.pos = pos subst.smap = smap + if check != nil { subst.check = check - subst.typMap = check.typMap - } else { + if typMap == nil { + typMap = check.typMap + } + } + if typMap == nil { // If we don't have a *Checker and its global type map, // use a local version. Besides avoiding duplicate work, // the type map prevents infinite recursive substitution // for recursive types (example: type T[P any] *T[P]). - subst.typMap = make(map[string]*Named) + typMap = make(map[string]*Named) } + subst.typMap = typMap return subst.typ(typ) } @@ -234,14 +241,15 @@ func (subst *subster) typ(typ Type) Type { // create a new named type and populate typMap to avoid endless recursion tname := NewTypeName(subst.pos, t.obj.pkg, t.obj.name, nil) - named := subst.check.newNamed(tname, t, t.Underlying(), t.TParams(), t.methods) // method signatures are updated lazily + t.load() + named := subst.check.newNamed(tname, t.orig, t.underlying, t.TParams(), t.methods) // method signatures are updated lazily named.targs = new_targs subst.typMap[h] = named - t.expand() // must happen after typMap update to avoid infinite recursion + t.expand(subst.typMap) // must happen after typMap update to avoid infinite recursion // do the substitution dump(">>> subst %s with %s (new: %s)", t.underlying, subst.smap, new_targs) - named.underlying = subst.typOrNil(t.Underlying()) + named.underlying = subst.typOrNil(t.underlying) dump(">>> underlying: %v", named.underlying) assert(named.underlying != nil) named.fromRHS = named.underlying // for cycle detection (Checker.validType) |