Preparse inner functions (new try)

test/cctest/test-parsing.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 20 matching lines @@
 
 #include <memory>
 
 #include "src/v8.h"
 
 #include "src/ast/ast-numbering.h"
 #include "src/ast/ast-value-factory.h"
 #include "src/ast/ast.h"
 #include "src/compiler.h"
 #include "src/execution.h"
+#include "src/flags.h"
 #include "src/isolate.h"
 #include "src/objects.h"
 #include "src/parsing/parse-info.h"
 #include "src/parsing/parser.h"
 #include "src/parsing/preparser.h"
 #include "src/parsing/rewriter.h"
 #include "src/parsing/scanner-character-streams.h"
 #include "src/parsing/token.h"
 #include "src/utils.h"
 
@@ skipping 3362 matching lines @@
           i::Scope* scope = info.literal()->scope();
           i::Scope* inner_scope = scope->inner_scope();
           DCHECK_NOT_NULL(inner_scope);
           DCHECK_NULL(inner_scope->sibling());
           const i::AstRawString* var_name =
               info.ast_value_factory()->GetOneByteString("x");
           i::Variable* var = inner_scope->Lookup(var_name);
           bool expected = outers[i].assigned || inners[j].assigned;
           CHECK(var != NULL);
           CHECK(var->is_used() || !expected);
-          CHECK((var->maybe_assigned() == i::kMaybeAssigned) == expected);
+          bool is_maybe_assigned = var->maybe_assigned() == i::kMaybeAssigned;
+          if (i::FLAG_lazy_inner_functions) {
+            // If we parse inner functions lazily, allow being pessimistic about
+            // maybe_assigned.
+            CHECK(is_maybe_assigned || (is_maybe_assigned == expected));
+          } else {
+            CHECK(is_maybe_assigned == expected);
+          }
         }
       }
     }
   }
 }
 
 namespace {
 
 int* global_use_counts = NULL;
 
@@ skipping 4894 matching lines @@
     const char* data[] = {
       "const arguments = 1",
       "let arguments",
       "var arguments",
       NULL
     };
     // clang-format on
     RunParserSyncTest(context_data, data, kSuccess);
   }
 }