From c90e785bb6fde02cc009f296332a1469fcc1261a Mon Sep 17 00:00:00 2001
From: Marek Polacek <polacek@redhat.com>
Date: Wed, 26 Jun 2024 17:55:21 -0400
Subject: [PATCH] c++: ICE with computed gotos [PR115469]

This is a low-prio crash on invalid code where we ICE on a VAR_DECL
with erroneous type.  I thought I'd try to avoid putting such decls
into ->names and ->names_in_scope but that sounds riskier than the
following cleanup.

	PR c++/115469

gcc/cp/ChangeLog:

	* decl.cc (automatic_var_with_nontrivial_dtor_p): New.
	(poplevel_named_label_1): Use it.
	(check_goto_1): Likewise.

gcc/testsuite/ChangeLog:

	* g++.dg/ext/label17.C: New test.
---
 gcc/cp/decl.cc                     | 20 ++++++++++++++++----
 gcc/testsuite/g++.dg/ext/label17.C | 18 ++++++++++++++++++
 2 files changed, 34 insertions(+), 4 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/ext/label17.C

diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index 03deb1493a4..c7457fae7b0 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -514,6 +514,20 @@ level_for_consteval_if (cp_binding_level *b)
 	  && IF_STMT_CONSTEVAL_P (b->this_entity));
 }
 
+/* True if T is a non-static VAR_DECL that has a non-trivial destructor.
+   See [stmt.dcl]/2.  */
+
+static bool
+automatic_var_with_nontrivial_dtor_p (const_tree t)
+{
+  if (error_operand_p (t))
+    return false;
+
+  return (VAR_P (t)
+	  && decl_storage_duration (CONST_CAST_TREE (t)) == dk_auto
+	  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (t)));
+}
+
 /* Update data for defined and undefined labels when leaving a scope.  */
 
 int
@@ -575,8 +589,7 @@ poplevel_named_label_1 (named_label_entry **slot, cp_binding_level *bl)
 		if (bl->kind == sk_catch)
 		  vec_safe_push (cg, get_identifier ("catch"));
 		for (tree d = use->names_in_scope; d; d = DECL_CHAIN (d))
-		  if (TREE_CODE (d) == VAR_DECL && !TREE_STATIC (d)
-		      && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (d)))
+		  if (automatic_var_with_nontrivial_dtor_p (d))
 		    vec_safe_push (cg, d);
 	      }
 
@@ -4003,8 +4016,7 @@ check_goto_1 (named_label_entry *ent, bool computed)
 	  tree end = b == level ? names : NULL_TREE;
 	  for (tree d = b->names; d != end; d = DECL_CHAIN (d))
 	    {
-	      if (TREE_CODE (d) == VAR_DECL && !TREE_STATIC (d)
-		  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (d)))
+	      if (automatic_var_with_nontrivial_dtor_p (d))
 		{
 		  if (!identified)
 		    {
diff --git a/gcc/testsuite/g++.dg/ext/label17.C b/gcc/testsuite/g++.dg/ext/label17.C
new file mode 100644
index 00000000000..076ef1f798e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/label17.C
@@ -0,0 +1,18 @@
+// PR c++/115469
+// { dg-do compile { target indirect_jumps } }
+// { dg-options "" }
+
+void
+fn1 ()
+{
+  b = &&c;    // { dg-error "not declared|not defined" }
+  goto *0;
+}
+
+void
+fn2 ()
+{
+c:
+  b = &&c;  // { dg-error "not declared" }
+  goto *0;
+}