compiler: handle unsafe conversion expression in escape analysis

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/192037

From-SVN: r275000

gcc/go/gofrontend/MERGE

@@ -1,4 +1,4 @@
-189ff44b2c26f29f41f0eb159e0d8f3fa508ecae
+5d15923ada640befb236d5fe94f0c724e98e99d7
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

gcc/go/gofrontend/escape.cc

@@ -1706,6 +1706,15 @@ Escape_analysis_assign::expression(Expression** pexpr)
       }
       break;
 
+    case Expression::EXPRESSION_UNSAFE_CONVERSION:
+      {
+        Unsafe_type_conversion_expression* uce =
+          (*pexpr)->unsafe_conversion_expression();
+        Node* expr_node = Node::make_node(uce->expr());
+        this->assign(n, expr_node);
+      }
+      break;
+
     case Expression::EXPRESSION_FIXED_ARRAY_CONSTRUCTION:
     case Expression::EXPRESSION_SLICE_CONSTRUCTION:
       {