Ping.
On Thu, Aug 29, 2024 at 04:15:41PM -0400, Marek Polacek wrote:
> Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk/14/13?
>
> -- >8 --
> Here we wrongly mark the reference temporary for g TREE_READONLY,
> so it's put in .rodata and so we can't modify its subobject even
> when the subobject is marked mutable. This is so since r9-869.
> r14-1785 fixed a similar problem, but not in set_up_extended_ref_temp.
>
> PR c++/116369
>
> gcc/cp/ChangeLog:
>
> * call.cc (set_up_extended_ref_temp): Don't mark a temporary
> TREE_READONLY if its type is TYPE_HAS_MUTABLE_P.
>
> gcc/testsuite/ChangeLog:
>
> * g++.dg/tree-ssa/initlist-opt7.C: New test.
> ---
> gcc/cp/call.cc | 4 +++-
> gcc/testsuite/g++.dg/tree-ssa/initlist-opt7.C | 13 +++++++++++++
> 2 files changed, 16 insertions(+), 1 deletion(-)
> create mode 100644 gcc/testsuite/g++.dg/tree-ssa/initlist-opt7.C
>
> diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc
> index fa7f05d76f6..d30f36d49ff 100644
> --- a/gcc/cp/call.cc
> +++ b/gcc/cp/call.cc
> @@ -13964,7 +13964,9 @@ set_up_extended_ref_temp (tree decl, tree expr,
> vec<tree, va_gc> **cleanups,
> init = cp_fully_fold (init);
> if (TREE_CONSTANT (init))
> {
> - if (literal_type_p (type) && CP_TYPE_CONST_NON_VOLATILE_P (type))
> + if (literal_type_p (type)
> + && CP_TYPE_CONST_NON_VOLATILE_P (type)
> + && !TYPE_HAS_MUTABLE_P (type))
> {
> /* 5.19 says that a constant expression can include an
> lvalue-rvalue conversion applied to "a glvalue of literal type
> diff --git a/gcc/testsuite/g++.dg/tree-ssa/initlist-opt7.C
> b/gcc/testsuite/g++.dg/tree-ssa/initlist-opt7.C
> new file mode 100644
> index 00000000000..2420db502a6
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/tree-ssa/initlist-opt7.C
> @@ -0,0 +1,13 @@
> +// PR c++/116369
> +// { dg-do run { target c++11 } }
> +
> +struct f{
> + mutable int t;
> +};
> +
> +const f &g = {1};
> +
> +int main()
> +{
> + g.t++;
> +}
>
> base-commit: 6bfeba12c86b4d0dae27d99b484f64774dd49398
> --
> 2.46.0
>
Marek
