minor fixes for script optimization, exporting of attr_name, script layout tweak

scripts/policy/protocols/ssl/ssl-log-ext.zeek

@@ -137,7 +137,7 @@ event ssl_extension_supported_versions(c: connection, is_client: bool, versions:
 		c$ssl$server_supported_version = versions[0];
 	}
 
-	event ssl_extension_psk_key_exchange_modes(c: connection, is_client: bool, modes: index_vec)
+event ssl_extension_psk_key_exchange_modes(c: connection, is_client: bool, modes: index_vec)
 	{
 	if ( ! c?$ssl || ! is_client )
 		return;

src/Attr.h

@@ -150,5 +150,8 @@ protected:
 // it will be returned in err_msg.
 extern bool check_default_attr(Attr* a, const TypePtr& type, bool global_var, bool in_record, std::string& err_msg);
 
+// Returns the script-level name associated with an attribute, e.g. "&default".
+extern const char* attr_name(AttrTag t);
+
 } // namespace detail
 } // namespace zeek

src/parse.y

@@ -132,6 +132,10 @@ std::string zeek::detail::current_module = GLOBAL_MODULE_NAME;
 
 bool is_export = false; // true if in an export {} block
 
+// Used to temporarily turn off "is_export". A stack because the need
+// to do so can nest.
+std::vector<bool> hold_is_export;
+
 // When parsing an expression for the debugger, where to put the result
 // (obviously not reentrant).
 extern Expr* g_curr_debug_expr;
@@ -586,7 +590,10 @@ expr:
 
 			if ( IsArithmetic($1->GetType()->Tag()) )
 				{
-				ExprPtr sum = make_intrusive<AddExpr>(lhs, rhs);
+				// Script optimization assumes that each AST
+				// node is distinct, hence the call to
+				// Duplicate() here.
+				ExprPtr sum = make_intrusive<AddExpr>(lhs->Duplicate(), rhs);
 
 				if ( sum->GetType()->Tag() != tag1 )
 					sum = make_intrusive<ArithCoerceExpr>(sum, tag1);
@@ -1584,8 +1591,24 @@ lambda_body:
 	;
 
 anonymous_function:
-		TOK_FUNCTION begin_lambda conditional_list lambda_body
+		TOK_FUNCTION
-			{ $$ = $4; }
+			{
+			// "is_export" is used in some contexts to determine
+			// whether a given newly seen identifier is a global.
+			// We're about parse a lambda body, for which all of
+			// the new identifiers should be locals, not globals,
+			// so we need to turn off "is_export" here.  We use
+			// a stack because lambdas can have additional lambdas
+			// inside their bodies.
+			hold_is_export.push_back(is_export);
+			is_export = false;
+			}
+		begin_lambda conditional_list lambda_body
+			{
+			is_export = hold_is_export.back();
+			hold_is_export.pop_back();
+			$$ = $5;
+			}
 	;
 
 begin_lambda: