From fdf9df9d55802e1d8ff0bd14585ea61b2bb9d798 Mon Sep 17 00:00:00 2001
From: Jakub Jelinek <jakub@redhat.com>
Date: Fri, 23 Feb 2024 18:55:12 +0100
Subject: [PATCH] c++: Fix ICE due to folding a call to constructor on
cdtor_returns_this arches (aka arm32) [PR113083]
When targetm.cxx.cdtor_returns_this () (aka on arm32 TARGET_AAPCS_BASED)
constructor is supposed to return this pointer, but when we cp_fold such
a call, we don't take that into account and just INIT_EXPR the object,
so we can later ICE during gimplification, because the expression doesn't
have the right type.
2024-02-23 Jakub Jelinek <jakub@redhat.com>
PR c++/113083
* cp-gimplify.cc (cp_fold): For targetm.cxx.cdtor_returns_this ()
wrap r into a COMPOUND_EXPR and return folded CALL_EXPR_ARG (x, 0).
* g++.dg/cpp0x/constexpr-113083.C: New test.
---
gcc/cp/cp-gimplify.cc | 10 ++++++++--
gcc/testsuite/g++.dg/cpp0x/constexpr-113083.C | 16 ++++++++++++++++
2 files changed, 24 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/constexpr-113083.C
diff --git a/gcc/cp/cp-gimplify.cc b/gcc/cp/cp-gimplify.cc
index 30e94797f9fd..f3baae6ade75 100644
--- a/gcc/cp/cp-gimplify.cc
+++ b/gcc/cp/cp-gimplify.cc
@@ -3412,9 +3412,15 @@ cp_fold (tree x, fold_flags_t flags)
if (DECL_CONSTRUCTOR_P (callee))
{
loc = EXPR_LOCATION (x);
- tree s = build_fold_indirect_ref_loc (loc,
- CALL_EXPR_ARG (x, 0));
+ tree a = CALL_EXPR_ARG (x, 0);
+ bool return_this = targetm.cxx.cdtor_returns_this ();
+ if (return_this)
+ a = cp_save_expr (a);
+ tree s = build_fold_indirect_ref_loc (loc, a);
r = cp_build_init_expr (s, r);
+ if (return_this)
+ r = build2_loc (loc, COMPOUND_EXPR, TREE_TYPE (x), r,
+ fold_convert_loc (loc, TREE_TYPE (x), a));
}
x = r;
break;
diff --git a/gcc/testsuite/g++.dg/cpp0x/constexpr-113083.C b/gcc/testsuite/g++.dg/cpp0x/constexpr-113083.C
new file mode 100644
index 000000000000..3829ac589c49
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/constexpr-113083.C
@@ -0,0 +1,16 @@
+// PR c++/113083
+// { dg-do compile { target c++11 } }
+// { dg-options "-Os" }
+
+struct A { constexpr A (); };
+
+void
+foo ()
+{
+ A b;
+}
+
+constexpr
+A::A ()
+{
+}
--
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