From: Marek Polacek <polacek@redhat.com>
Date: Tue, 16 Jan 2024 20:49:46 +0000 (-0500)
Subject: c++: fix ICE with xobj in destructor [PR113340]
X-Git-Tag: basepoints/gcc-15~1974
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ac219d524ace47eea5bf5404b267e22950f44030;p=thirdparty%2Fgcc.git

c++: fix ICE with xobj in destructor [PR113340]

Here we crash in maybe_retrofit_in_chrg on an invalid dtor
with explicit this.  Such member functions do not get converted
to METHOD_TYPE.  If a dtor gets parameters, we reset arg_types
to void_list_node in grokdeclarator.  This results in m_r_in_c
receiving:
  void <T8d> (void)
and crashing on
  parms = DECL_CHAIN (DECL_ARGUMENTS (fn));

This patch avoids the ICE by resetting is_xobj_member_function after
emitting the error.  Then m_r_in_c gets
  void S::<T40b> (struct S *)
which does not cause a crash.

	PR c++/113340

gcc/cp/ChangeLog:

	* decl.cc (grokdeclarator) <case cdk_function>: Clear
	is_xobj_member_function in case of an error.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp23/explicit-obj-diagnostics9.C: New test.
---

diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index b10a72a87bf0..2e5702971c4c 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -13743,6 +13743,7 @@ grokdeclarator (const cp_declarator *declarator,
 			  "destructors may not have parameters");
 		arg_types = void_list_node;
 		parms = NULL_TREE;
+		is_xobj_member_function = false;
 	      }
 
 	    type = build_function_type (type, arg_types);
diff --git a/gcc/testsuite/g++.dg/cpp23/explicit-obj-diagnostics9.C b/gcc/testsuite/g++.dg/cpp23/explicit-obj-diagnostics9.C
new file mode 100644
index 000000000000..d420793c1e1a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp23/explicit-obj-diagnostics9.C
@@ -0,0 +1,6 @@
+// PR c++/113340
+// { dg-do compile { target c++23 } }
+
+struct S {
+  ~S(this S &) = default; // { dg-error "destructors may not have parameters" }
+};