bpo-40555: Check for p->error_indicator in loop rules after the main loop is done (GH-19986)

3 files changed, 37 insertions, 28 deletions

diff --git a/Lib/test/test_eof.py b/Lib/test/test_eof.py
index 9ef8eb1187..bebad31061 100644
--- a/Lib/test/test_eof.py
+++ b/Lib/test/test_eof.py
@@ -26,6 +26,15 @@ class EOFTestCase(unittest.TestCase):
         else:
             raise support.TestFailed
 
+    def test_eof_with_line_continuation(self):
+        expect = "unexpected EOF while parsing (<string>, line 1)"
+        try:
+            compile('"\\xhh" \\',  '<string>', 'exec', dont_inherit=True)
+        except SyntaxError as msg:
+            self.assertEqual(str(msg), expect)
+        else:
+            raise support.TestFailed
+
     def test_line_continuation_EOF(self):
         """A continuation at the end of input must be an error; bpo2180."""
         expect = 'unexpected EOF while parsing (<string>, line 1)'
diff --git a/Parser/pegen/parse.c b/Parser/pegen/parse.c
index 3a08abbca5..ae86841e86 100644
--- a/Parser/pegen/parse.c
+++ b/Parser/pegen/parse.c
@@ -11437,7 +11437,7 @@ _loop1_11_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -11876,7 +11876,7 @@ _loop1_22_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -12252,7 +12252,7 @@ _loop1_31_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -12911,7 +12911,7 @@ _loop1_47_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -13267,7 +13267,7 @@ _loop1_56_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -13369,7 +13369,7 @@ _loop1_58_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -13422,7 +13422,7 @@ _loop1_59_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -13475,7 +13475,7 @@ _loop1_60_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -13577,7 +13577,7 @@ _loop1_62_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -13679,7 +13679,7 @@ _loop1_64_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -13781,7 +13781,7 @@ _loop1_66_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -13834,7 +13834,7 @@ _loop1_67_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14007,7 +14007,7 @@ _loop1_71_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14145,7 +14145,7 @@ _loop1_74_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14345,7 +14345,7 @@ _loop1_78_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14447,7 +14447,7 @@ _loop1_80_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14500,7 +14500,7 @@ _loop1_81_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14553,7 +14553,7 @@ _loop1_82_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14655,7 +14655,7 @@ _loop1_84_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14757,7 +14757,7 @@ _loop1_86_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14859,7 +14859,7 @@ _loop1_88_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14912,7 +14912,7 @@ _loop1_89_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -14965,7 +14965,7 @@ _loop1_90_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -15018,7 +15018,7 @@ _loop1_91_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -15358,7 +15358,7 @@ _loop1_99_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -15567,7 +15567,7 @@ _loop1_104_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
@@ -17165,7 +17165,7 @@ _loop1_145_rule(Parser *p)
         }
         p->mark = mark;
     }
-    if (n == 0) {
+    if (n == 0 || p->error_indicator) {
         PyMem_Free(children);
         return NULL;
     }
diff --git a/Tools/peg_generator/pegen/c_generator.py b/Tools/peg_generator/pegen/c_generator.py
index 3bf6d9ed6a..b7a9942c2f 100644
--- a/Tools/peg_generator/pegen/c_generator.py
+++ b/Tools/peg_generator/pegen/c_generator.py
@@ -525,7 +525,7 @@ class CParserGenerator(ParserGenerator, GrammarVisitor):
                 rulename=node.name if memoize else None,
             )
             if is_repeat1:
-                self.print("if (n == 0) {")
+                self.print("if (n == 0 || p->error_indicator) {")
                 with self.indent():
                     self.print("PyMem_Free(children);")
                     self.print("return NULL;")