kern/56494: uvm_loanobjpages at uvm_loan.c, error is uninitialized

[hashikaw%mail.ru@localhost]

>Number:         56494
>Category:       kern
>Synopsis:       uvm_loanobjpages at uvm_loan.c, error is uninitialized
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Nov 11 18:30:00 +0000 2021
>Originator:     Kouichi Hashikawa
>Release:        9.9.92, 9-RELEASE
>Organization:
>Environment:
>Description:
I compile kernel with COPTS="-O -fno-omit-frame-pointer" (not -O2), then got error,

/current/netbsd/c/src/sys/uvm/uvm_loan.c:583:9: error: 'error' may be used uninitialized in this function [-Werror=maybe-uninitialized]
  583 |  return error;
      |         ^~~~~
cc1: all warnings being treated as errors

I think NetBSD-9 has same problem.

>How-To-Repeat:

>Fix: