Go patch committed: Propagate array length error marker

[Ian Lance Taylor via Gcc-patches]

This patch to the Go frontend propagates the array length error marker
farther, to avoid a compiler crash on invalid code.  This fixes
https://go.dev/issue/53639.  Bootstrapped and ran Go testsuite on
x86_64-pc-linux-gnu.  Committed to mainline.

Ian

c70a48a8f8f6a43b35f783b5672c9a3c0a363c31
diff --git a/gcc/go/gofrontend/MERGE b/gcc/go/gofrontend/MERGE
index 461e2fdf271..7c5c45672d7 100644
--- a/gcc/go/gofrontend/MERGE
+++ b/gcc/go/gofrontend/MERGE
@@ -1,4 +1,4 @@
-a209dca9ec918535977dcab99fd9bb60986ffacd
+d295a0a2c96c0f7c3abd94fea3aa4e2303bf2af2
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.
diff --git a/gcc/go/gofrontend/expressions.cc b/gcc/go/gofrontend/expressions.cc
index 00d35a965a9..2492d9fe735 100644
--- a/gcc/go/gofrontend/expressions.cc
+++ b/gcc/go/gofrontend/expressions.cc
@@ -8486,6 +8486,11 @@ Builtin_call_expression::do_flatten(Gogo* gogo, 
Named_object* function,
             pa != this->args()->end();
             ++pa)
          {
+           if ((*pa)->is_error_expression())
+             {
+               go_assert(saw_errors());
+               return Expression::make_error(loc);
+             }
            if ((*pa)->is_nil_expression())
              {
                Expression* nil = Expression::make_nil(loc);
@@ -13391,6 +13396,7 @@ Array_index_expression::do_check_types(Gogo*)
   if (array_type == NULL)
     {
       go_assert(this->array_->type()->is_error());
+      this->set_is_error();
       return;
     }
 
diff --git a/gcc/go/gofrontend/types.cc b/gcc/go/gofrontend/types.cc
index 4995283bb60..9f34801f695 100644
--- a/gcc/go/gofrontend/types.cc
+++ b/gcc/go/gofrontend/types.cc
@@ -7429,7 +7429,10 @@ bool
 Array_type::do_verify()
 {
   if (this->element_type()->is_error_type())
-    return false;
+    {
+      this->set_is_error();
+      return false;
+    }
   if (!this->verify_length())
     {
       this->length_ = Expression::make_error(this->length_->location());