[Python] try to add keyword to python's pass_stmt like book cpython internals

I am trying book cpython internals's example: cpython internals ,you can find it at the page 72, an example that add keyword proceed to pass statement. I am using the newest version of cpython(3.14)instead of the book's.There are some differences in the source code,but the whole structure is similar.

I do the folloing: add new keyword 'xxxxxx' to the simple_stmt.

simple_stmt[stmt_ty] (memo):
| assignment
| &"type" type_alias
| e=star_expressions { _PyAST_Expr(e, EXTRA) }
| &'return' return_stmt
| &('import' | 'from') import_stmt
| &'raise' raise_stmt
| &('pass'|'xxxxxx') pass_stmt
| &'del' del_stmt
| &'yield' yield_stmt
| &'assert' assert_stmt
| &'break' break_stmt
| &'continue' continue_stmt
| &'global' global_stmt
| &'nonlocal' nonlocal_stmt


and add the new keyword case in the pass_stmt:

pass_stmt[stmt_ty]:
| 'pass' { _PyAST_Pass(EXTRA) }
| 'xxxxxx' { _PyAST_Pass(EXTRA) }


this works. I can use xxxxxx to replace pass in the new python.But when i try this:

pass_stmt[stmt_ty]:
| ('pass'|'xxxxxx') { _PyAST_Pass(EXTRA) }


it fails:

Parser/parser.c: In function ‘pass_stmt_rule’:
Parser/parser.c:2870:18: error: assignment to ‘stmt_ty’ {aka ‘struct _stmt *’} from incompatible pointer type ‘Token *’ [-Wincompatible-pointer-types]
2870 | _res = _keyword;
| ^
Parser/parser.c:2889:18: error: assignment to ‘stmt_ty’ {aka ‘struct _stmt *’} from incompatible pointer type ‘Token *’ [-Wincompatible-pointer-types]
2889 | _res = _keyword;
|


It seemed that the second try produced code that just returned the keyword,like"xxxxxx" or "pass",not _PyAST_Pass(EXTRA) .Why?

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