commit 6c3752315dc9b82d0f3f3ac646a1e7376818f84a
author Ian Lance Taylor <iant@golang.org> Wed Jun 22 16:40:24 2022 -0700
committer Ian Lance Taylor <iant@golang.org> Thu Jun 23 19:20:33 2022 +0000
tree 95a84fb7416081668eef06c95cffcc343ae4402d
parent 77821de1a149c2e6ef9c154ae384c16292173039

compiler: unalias types for hash/equality functions

Test case is https://go.dev/cl/413694.

Fixes golang/go#52846

Change-Id: I9dc883ba18b3ae1697acfc1b8a78560294cf5c30
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/413660
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>

go/gogo.cc

diff --git a/go/gogo.cc b/go/gogo.cc
index d35c6ba..e13df0d 100644
--- a/go/gogo.cc
+++ b/go/gogo.cc
@@ -2811,7 +2811,7 @@
 
     case Type::TYPE_MAP:
       {
-	Type* key_type = t->map_type()->key_type();
+	Type* key_type = t->map_type()->key_type()->unalias();
 	if (key_type->needs_specific_type_functions(this->gogo_))
 	  key_type->hash_function(this->gogo_, NULL);
       }

go/types.cc

diff --git a/go/types.cc b/go/types.cc
index eb3afd9..39aea76 100644
--- a/go/types.cc
+++ b/go/types.cc
@@ -1764,6 +1764,9 @@
 Named_object*
 Type::hash_function(Gogo* gogo, Function_type* hash_fntype)
 {
+  if (this->named_type() != NULL)
+    go_assert(!this->named_type()->is_alias());
+
   if (!this->is_comparable())
     return NULL;
 
@@ -2067,6 +2070,9 @@
 Named_object*
 Type::equal_function(Gogo* gogo, Named_type* name, Function_type* equal_fntype)
 {
+  if (this->named_type() != NULL)
+    go_assert(!this->named_type()->is_alias());
+
   // If the unaliased type is not a named type, then the type does not
   // have a name after all.
   if (name != NULL)
@@ -6700,7 +6706,8 @@
       subkey = Expression::make_cast(key_arg_type, subkey, bloc);
 
       // Get the hash function to use for the type of this field.
-      Named_object* hash_fn = pf->type()->hash_function(gogo, hash_fntype);
+      Named_object* hash_fn =
+	pf->type()->unalias()->hash_function(gogo, hash_fntype);
 
       // Call the hash function for the field, passing retval as the seed.
       ref = Expression::make_temporary_reference(retval, bloc);
@@ -7553,8 +7560,8 @@
   gogo->start_block(bloc);
 
   // Get the hash function for the element type.
-  Named_object* hash_fn = this->element_type_->hash_function(gogo,
-							     hash_fntype);
+  Named_object* hash_fn =
+    this->element_type_->unalias()->hash_function(gogo, hash_fntype);
 
   // Get a pointer to this element in the loop.
   Expression* subkey = Expression::make_temporary_reference(key, bloc);
@@ -8441,8 +8448,8 @@
   ++p;
   go_assert(p->is_field_name("hasher"));
   Function_type* hasher_fntype = p->type()->function_type();
-  Named_object* hasher_fn = this->key_type_->hash_function(gogo,
-							   hasher_fntype);
+  Named_object* hasher_fn =
+    this->key_type_->unalias()->hash_function(gogo, hasher_fntype);
   if (hasher_fn == NULL)
     vals->push_back(Expression::make_cast(hasher_fntype,
 					  Expression::make_nil(bloc),