[3.10] bpo-46004: Fix error location for loops with invalid targets (GH-29959). (GH-29961)

(cherry picked from commit 1c7a1c3) Co-authored-by: Pablo Galindo Salgado <Pablogsal@gmail.com>

Author: pablogsal

Lib/test/test_exceptions.py

@@ -234,6 +234,7 @@ def testSyntaxErrorOffset(self):
  check("ages = {'Alice'=22, 'Bob'=23}", 1, 16)
  check('match ...:\n case {**rest, "key": value}:\n ...', 2, 19)
  check("[a b c d e f]", 1, 2)
+ check("for x yfff:", 1, 7)
 
  # Errors thrown by compile.c
  check('class foo:return 1', 1, 11)

Misc/NEWS.d/next/Core and Builtins/2021-12-07-11-24-24.bpo-46004.TTEU1p.rst

@@ -0,0 +1,2 @@
+Fix the :exc:`SyntaxError` location for errors involving for loops with
+invalid targets. Patch by Pablo Galindo

Parser/pegen.h

@@ -321,8 +321,9 @@ _RAISE_SYNTAX_ERROR_INVALID_TARGET(Parser *p, TARGETS_TYPE type, void *e)
  msg,
  _PyPegen_get_expr_name(invalid_target)
  );
+ return RAISE_SYNTAX_ERROR_KNOWN_LOCATION(invalid_target, "invalid syntax");
  }
- return RAISE_SYNTAX_ERROR("invalid syntax");
+ return NULL;
 }
 
 void *_PyPegen_arguments_parsing_error(Parser *, expr_ty);