From: Andrew Pinski <quic_apinski@quicinc.com>
Date: Sat, 23 Nov 2024 21:42:47 +0000 (-0800)
Subject: gimplefe: Fix handling of ')'/'}' after a parse error [PR117741]
X-Git-Tag: basepoints/gcc-16~3920
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e9f3eb8493c66da143561d6b866c4b3204e42574;p=thirdparty%2Fgcc.git

gimplefe: Fix handling of ')'/'}' after a parse error [PR117741]

The problem here is c_parser_skip_until_found stops at a closing nesting
delimiter without consuming it. So if we don't consume it in
c_parser_gimple_compound_statement, we would go into an infinite loop. The C
parser similar code in c_parser_statement_after_labels to handle this specific
case too.

	PR c/117741

gcc/c/ChangeLog:

	* gimple-parser.cc (c_parser_gimple_compound_statement): Handle
	CPP_CLOSE_PAREN/CPP_CLOSE_SQUARE with an error and skipping the token.

gcc/testsuite/ChangeLog:

	* gcc.dg/gimplefe-54.c: New test.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>
---

diff --git a/gcc/c/gimple-parser.cc b/gcc/c/gimple-parser.cc
index 81f3921c8760..4763cf23313b 100644
--- a/gcc/c/gimple-parser.cc
+++ b/gcc/c/gimple-parser.cc
@@ -664,6 +664,16 @@ c_parser_gimple_compound_statement (gimple_parser &parser, gimple_seq *seq)
 	    break;
 	  }
 
+	case CPP_CLOSE_PAREN:
+	case CPP_CLOSE_SQUARE:
+	  /* Avoid infinite loop in error recovery:
+	     c_parser_skip_until_found stops at a closing nesting
+	     delimiter without consuming it, but here we need to consume
+	     it to proceed further.  */
+	  c_parser_error (parser, "expected statement");
+	  c_parser_consume_token (parser);
+	break;
+
 	default:
 expr_stmt:
 	  c_parser_gimple_statement (parser, seq);
diff --git a/gcc/testsuite/gcc.dg/gimplefe-54.c b/gcc/testsuite/gcc.dg/gimplefe-54.c
new file mode 100644
index 000000000000..71a49ac39c28
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/gimplefe-54.c
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+/* { dg-options "-fgimple" } */
+
+/* PR c/117741 */
+/* Make sure after a parsing error we
+   don't go into an infinite loop. */
+
+int i;
+void __GIMPLE foo() {
+  i = ) /* { dg-error "" } */