Re: [PATCH] c++: abi_tag attribute on templates [PR109715]

[Jason Merrill <jason@redhat.com>]

On 12/14/23 14:17, Patrick Palka wrote:
> Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
> trunk?  Do we want to condition this on abi_check (19)?

I think we do, sadly.

> -- >8 --
> 
> As with other declaration attributes, we need to look through
> TEMPLATE_DECL when looking up the abi_tag attribute.
> 
> 	PR c++/109715
> 
> gcc/cp/ChangeLog:
> 
> 	* mangle.cc (get_abi_tags): Look through TEMPLATE_DECL.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* g++.dg/abi/abi-tag25.C: New test.
> ---
>   gcc/cp/mangle.cc                     |  3 +++
>   gcc/testsuite/g++.dg/abi/abi-tag25.C | 17 +++++++++++++++++
>   2 files changed, 20 insertions(+)
>   create mode 100644 gcc/testsuite/g++.dg/abi/abi-tag25.C
> 
> diff --git a/gcc/cp/mangle.cc b/gcc/cp/mangle.cc
> index 0684f0e6038..1fbd879c116 100644
> --- a/gcc/cp/mangle.cc
> +++ b/gcc/cp/mangle.cc
> @@ -527,6 +527,9 @@ get_abi_tags (tree t)
>     if (!t || TREE_CODE (t) == NAMESPACE_DECL)
>       return NULL_TREE;
>   
> +  if (TREE_CODE (t) == TEMPLATE_DECL && DECL_TEMPLATE_RESULT (t))
> +    t = DECL_TEMPLATE_RESULT (t);
> +
>     if (DECL_P (t) && DECL_DECLARES_TYPE_P (t))
>       t = TREE_TYPE (t);
>   
> diff --git a/gcc/testsuite/g++.dg/abi/abi-tag25.C b/gcc/testsuite/g++.dg/abi/abi-tag25.C
> new file mode 100644
> index 00000000000..9847f0dccc8
> --- /dev/null
> +++ b/gcc/testsuite/g++.dg/abi/abi-tag25.C
> @@ -0,0 +1,17 @@
> +// PR c++/109715
> +// { dg-do compile { target c++11 } }
> +
> +template<class T>
> +[[gnu::abi_tag("foo")]] void fun() { }
> +
> +template void fun<int>();
> +
> +#if __cpp_variable_templates
> +template<class T>
> +[[gnu::abi_tag("foo")]] int var = 0;
> +
> +template int var<int>;
> +#endif
> +
> +// { dg-final { scan-assembler "_Z3funB3fooIiEvv" } }
> +// { dg-final { scan-assembler "_Z3varB3fooIiE" { target c++14 } } }