[Bug tree-optimization/121049] [16 regression] timezone-data miscompiled with -O3 -march=x86-64-v4 -mtune=znver4 since r16-2088-ge9079e4f43d135

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121049

Richard Biener  changed:

   What|Removed |Added

   Assignee|unassigned at gcc dot gnu.org  |rguenth at gcc dot 
gnu.org
 Status|NEW |ASSIGNED

--- Comment #12 from Richard Biener  ---
I will look at this at some point but will prioritize the issues also affecting
GCC 15 first.

[Bug tree-optimization/121049] [16 regression] timezone-data miscompiled with -O3 -march=x86-64-v4 -mtune=znver4 since r16-2088-ge9079e4f43d135

[rguenther at suse dot de via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121049

--- Comment #11 from rguenther at suse dot de  ---
On Sun, 13 Jul 2025, sjames at gcc dot gnu.org wrote:

> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121049
> 
> --- Comment #9 from Sam James  ---
> Yes, I tried to go further but the compiler hangs with the needed param before
> that commit for a large part of the range.

Probably related to PR120927 then.

[Bug tree-optimization/121049] [16 regression] timezone-data miscompiled with -O3 -march=x86-64-v4 -mtune=znver4 since r16-2088-ge9079e4f43d135

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121049

Andrew Pinski  changed:

   What|Removed |Added

 Target||x86_64

--- Comment #10 from Andrew Pinski  ---
Unlike the other one, `-O3 -march=x86-64-v4 --param
vect-partial-vector-usage=1` still works.

[Bug tree-optimization/121049] [16 regression] timezone-data miscompiled with -O3 -march=x86-64-v4 -mtune=znver4 since r16-2088-ge9079e4f43d135

[sjames at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121049

--- Comment #9 from Sam James  ---
Yes, I tried to go further but the compiler hangs with the needed param before
that commit for a large part of the range.

[Bug tree-optimization/121049] [16 regression] timezone-data miscompiled with -O3 -march=x86-64-v4 -mtune=znver4 since r16-2088-ge9079e4f43d135

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121049

--- Comment #8 from Andrew Pinski  ---
(In reply to Sam James from comment #7)
> r16-2088-ge9079e4f43d135

This looks like it just exposed the issue with a costing model change in the
backend.

[Bug tree-optimization/121049] [16 regression] timezone-data miscompiled with -O3 -march=x86-64-v4 -mtune=znver4 since r16-2088-ge9079e4f43d135

[sjames at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121049

Sam James  changed:

   What|Removed |Added

   Keywords|needs-bisection |
 CC||rguenth at gcc dot gnu.org
Summary|[16 regression] |[16 regression]
   |timezone-data miscompiled   |timezone-data miscompiled
   |with -O3 -march=x86-64-v4   |with -O3 -march=x86-64-v4
   |-mtune=znver4   |-mtune=znver4 since
   ||r16-2088-ge9079e4f43d135

--- Comment #7 from Sam James  ---
r16-2088-ge9079e4f43d135