> On 24 Apr 2025, at 11:34, Jakub Jelinek <ja...@redhat.com> wrote:
>
> On Thu, Apr 24, 2025 at 11:27:36AM +0200, Jakub Jelinek wrote:
>>> This is a thinko in the logic for handling the default -flto-partition=
>>> arguments. We should override it to balanced only if it stayed as default
>>> up to that point. We should also be testing opts instead of opts_set here.
>>>
>>> Bootstrapped and tested on aarch64-none-linux-gnu.
>>>
>>> Ok for trunk? Sorry for the late patch, but I guess we want this in the GCC
>>> 15 branch as well.
>>> Thanks,
>>> Kyrill
>>>
>>> Signed-off-by: Kyrylo Tkachov <ktkac...@nvidia.com>
>>>
>>> gcc/
>>>
>>> * opts.cc (finish_options): Check for == against LTO_PARTITION_DEFAULT
>>> before setting LTO_PARTITION_BALANCED.
>>
>> I think
>> opts_set->x_flag_lto_partition = opts->x_flag_lto_partition =
>> LTO_PARTITION_BALANCED;
>>
>> is also wrong.
>> opts_set should have bool in whatever type the field has, so I think it
>> should be
>> {
>> opts->x_flag_lto_partition = LTO_PARTITION_BALANCED;
>> opts_set->x_flag_lto_partition = true;
>> }
>> (or maybe just opts->x_flag_lto_partition = LTO_PARTITION_BALANCED; alone?).
>> LTO_PARTITION_BALANCED is 2...
>
> In fact, I wonder why LTO_PARTITION_DEFAULT and -flto-partition=default has
> been added at all (and it isn't documented).
It was not intended to be exposed to users, it was used as a mechanism to check
if flto-partition is explicitly set.
> I'd have expected instead of the LTO_PARTITION_DEFAULT checks one should be
> testing !opts_set->x_flag_lto_partition (i.e. -flto-partition=balanced
> should be the default, but when not specified explicitly, it would really
> match that
> error ("%<-fipa-reorder-for-locality%> is incompatible with"
>
>
> " an explicit %qs option", "-flto-partition");
>
>
> error wording (right now -fipa-reorder-for-locality -flto-partition=default
> is explicit, yet no error is emittetd).
Yes, I think I was confused about the use of opts_set. This is overly
convoluted.
So something like this?
Checked manually that the required error is given, the default selected
partitioning is balanced, and an explicit -flto-partition=max selects it
properly.
Running a full bootstrap cycle now.
Thanks,
Kyrill
0001-opts.cc-Simplify-handling-of-explicit-flto-partition.patch
Description: 0001-opts.cc-Simplify-handling-of-explicit-flto-partition.patch
