On Mon, Dec 04, 2023 at 01:19:21PM +0000, Richard Sandiford wrote:
> >> (that takes a size) explicitly, rather than rely on template resolution.
> >> In the example above this looks like:
> >>
> >> array_slice<int> t (table, 3);
> >>
> >> or equivalently
> >>
> >> array_slice<int> t = array_slice<int>(table, 3);
> >>
> >> or equivalently
> >>
> >> array_slice<int> t = array_slice<int>(table, ARRAY_SIZE (table));
> >
> > Taking c-decl.cc as an arbitrary example, it seems to be enough to change:
> >
> > const scoped_attribute_specs std_attribute_table =
> > {
> > nullptr, std_attributes
> > };
> >
> > to:
> >
> > const scoped_attribute_specs std_attribute_table =
> > {
> > nullptr, { std_attributes }
> > };
> >
> > which seems less ugly than the explicit constructors.
> >
> > But if we're going to do this, we should do it across the board,
> > not just for x86.
>
> Here's an attempt to do that. Tested so far by building
> aarch64-linux-gnu (which has target attributes) and frv-elf
> (which doesn't) with GCC 4.8.
>
> OK if further testing passes?
>
> Richard
>
> ---
>
> GCC 5 and earlier applied array-to-pointer decay too early,
> which affected the new attribute namespace code. A reduced
> example of the construct that the attribute code uses is:
>
> struct S { template<__SIZE_TYPE__ N> S(int (&)[N]); };
> struct T { int a; S b; };
> int a[] = { 1 };
> T t = { 1, a };
>
> This was fixed by f85e1317f8ea933f5c615680353bd646f480f7d3
> (PR 16333 et al).
>
> This patch tries to add a minimally-invasive workaround.
>
> gcc/ada/
> * gcc-interface/utils.cc (gnat_internal_attribute_table): Add extra
> braces to work around PR 16333 in older compilers.
>
> gcc/
> * attribs.cc (handle_ignored_attributes_option): Add extra
> braces to work around PR 16333 in older compilers.
> * config/arm/arm.cc (arm_gnu_attribute_table): Likewise.
> * config/i386/i386-options.cc (ix86_gnu_attribute_table): Likewise.
> * config/ia64/ia64.cc (ia64_gnu_attribute_table): Likewise.
> * config/rs6000/rs6000.cc (rs6000_gnu_attribute_table): Likewise.
> * target-def.h (TARGET_GNU_ATTRIBUTES): Likewise.
> * genhooks.cc (emit_init_macros): Likewise, when emitting the
> instantiation of TARGET_ATTRIBUTE_TABLE.
> * langhooks-def.h (LANG_HOOKS_INITIALIZER): Likewise, when
> instantiating LANG_HOOKS_ATTRIBUTE_TABLE.
> (LANG_HOOKS_ATTRIBUTE_TABLE): Define to be empty by default.
> * target.def (attribute_table): Likewise.
>
> gcc/c-family/
> * c-attribs.cc (c_common_gnu_attribute_table): Add extra
> braces to work around PR 16333 in older compilers.
>
> gcc/c/
> * c-decl.cc (std_attribute_table): Add extra braces to work
> around PR 16333 in older compilers.
>
> gcc/cp/
> * tree.cc (cxx_gnu_attribute_table): Add extra braces to work
> around PR 16333 in older compilers.
>
> gcc/d/
> * d-attribs.cc (d_langhook_common_attribute_table): Add extra braces
> to work around PR 16333 in older compilers.
> (d_langhook_gnu_attribute_table): Likewise.
>
> gcc/fortran/
> * f95-lang.cc (gfc_gnu_attribute_table): Add extra braces to work
> around PR 16333 in older compilers.
>
> gcc/jit/
> * dummy-frontend.cc (jit_gnu_attribute_table): Add extra braces
> to work around PR 16333 in older compilers.
> (jit_format_attribute_table): Likewise.
>
> gcc/lto/
> * lto-lang.cc (lto_gnu_attribute_table): Add extra braces to work
> around PR 16333 in older compilers.
> (lto_format_attribute_table): Likewise.
LGTM.
Jakub
