https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78112
--- Comment #11 from ro at CeBiTec dot Uni-Bielefeld.DE <ro at CeBiTec dot
Uni-Bielefeld.DE> ---
> --- Comment #9 from Pierre-Marie de Rodat <derodat at adacore dot com> ---
[...]
> My analysis so far is that gen_subprogram_die is supposed to be called a very
> specific number of times for each function and my change from 2016-10-12 made
> it run more times, so it unintentionally added some attributes more than just
> once. The following patch seems to restore call count to what we had
> previously:
>
> diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
> index 78a2979..a85ab3b 100644
> --- a/gcc/dwarf2out.c
> +++ b/gcc/dwarf2out.c
> @@ -23909,11 +23909,11 @@ dwarf2out_early_global_decl (tree decl)
> if (!DECL_STRUCT_FUNCTION (decl))
> goto early_decl_exit;
>
> - /* For nested functions, emit DIEs for the parents first so that all
> - nested DIEs are generated at the proper scope in the first
> - shot. */
> + /* For nested functions, make sure we have DIEs for the parents
> first
> + so that all nested DIEs are generated at the proper scope in the
> + first shot. */
> tree context = decl_function_context (decl);
> - if (context != NULL)
> + if (context != NULL && lookup_decl_die (context) == NULL)
> {
> current_function_decl = context;
> dwarf2out_decl (context);
>
> I’m currently bootstrapping+regtesting it on x86_64-linux. I tried to come up
> with a regression testcase for it, but I can’t find a human-friendly regexp
> for
> scan-assembler-times to check that we don’t have multiple attributes per tag.
> So for local testing, I wrote a Python3 script to use the pyelftools library.
> I’ll file it right after sending this message if others need to use it.
I've just completed a x86_64-apple-darwin16.3.0 bootstrap with your
patch included and all the libstdc++ failues are gone indeed.
Thanks.
Rainer
