port-alpha/60356: pie tests are failing on alpha

["campbell+netbsd%mumble.net@localhost via gnats" <gnats-admin%NetBSD.org@localhost>]

>Number:         60356
>Category:       port-alpha
>Synopsis:       pie tests are failing on alpha
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    port-alpha-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Jun 23 16:30:00 +0000 2026
>Originator:     Taylor R Campbell
>Release:        current
>Organization:
The NetPIE Foundalphabug, Inc.
>Environment:
>Description:
https://releng.netbsd.org/b5reports/alpha/2026/2026.06.23.06.42.26/test.html#usr.bin_c++_t_call_once_call_once_pie

Test case: usr.bin/c++/t_call_once/call_once_pie

Duration: 15.111519 seconds
Termination reason

FAILED: atf-check failed; see the output of the test for details
Standard output stream

Executing command [ c++ -fpie -pie -o call_once test.cpp -pthread ]
Executing command [ ./call_once ]

Standard error stream

Fail: program did not exit cleanly
stdout:

stderr:
terminate called after throwing an instance of 'std::system_error'
  what():  Unknown error: -1

>How-To-Repeat:
cd /usr/tests/usr.bin/c++ && atf-run | atf-report
>Fix:
Yes, please!