runtime: `unexpected return pc for runtime.sigpanic` on openbsd-amd64-68

[bcmills]

unexpected fault address 0xc0014de278
fatal error: fault
[signal SIGSEGV: segmentation violation code=0x2 addr=0xc0014de278 pc=0xc0014de278]

goroutine 13246 [running]:
runtime.throw({0x6bf48f?, 0x727230?})
    /tmp/workdir/go/src/runtime/panic.go:1000 +0x71 fp=0xc0014de208 sp=0xc0014de1d8 pc=0x434171
runtime: g 13246: unexpected return pc for runtime.sigpanic called from 0xc0014de278
stack: frame={sp:0xc0014de208, fp:0xc0014de258} stack=[0xc0014d8000,0xc0014e0000)
0x000000c0014de108:  0x0000000000452c94 <runtime.write1+0x0000000000000034>  0x0000000000000002 
0x000000c0014de118:  0x000000c0014de150  0x000000c0014de150 
0x000000c0014de128:  0x000000000045567b <runtime.write+0x000000000000003b>  0x0000000000000002 
0x000000c0014de138:  0x00000000006bed46  0x0000000000000001 
0x000000c0014de148:  0x0000000000000001  0x000000c0014de188 
0x000000c0014de158:  0x0000000000435b32 <runtime.gwrite+0x00000000000000f2>  0x00000000006bed46 
0x000000c0014de168:  0x0000000000000001  0x0000000000000001 
0x000000c0014de178:  0x000000c0014de1ec  0x000000000000000c 
0x000000c0014de188:  0x000000c0014de1d8  0x000000000046358e <runtime.systemstack+0x000000000000002e> 
0x000000c0014de198:  0x00000000004343b0 <runtime.fatalthrow+0x0000000000000050>  0x000000c0014de1a8 
0x000000c0014de1a8:  0x00000000004343e0 <runtime.fatalthrow.func1+0x0000000000000000>  0x000000c0001de340 
0x000000c0014de1b8:  0x0000000000434171 <runtime.throw+0x0000000000000071>  0x000000c0014de1d8 
0x000000c0014de1c8:  0x000000c0014de1f8  0x0000000000434171 <runtime.throw+0x0000000000000071> 
0x000000c0014de1d8:  0x000000c0014de1e0  0x00000000004341a0 <runtime.throw.func1+0x0000000000000000> 
0x000000c0014de1e8:  0x00000000006bf48f  0x0000000000000005 
0x000000c0014de1f8:  0x000000c0014de248  0x0000000000449e85 <runtime.sigpanic+0x0000000000000305> 
0x000000c0014de208: <0x00000000006bf48f  0x0000000000727230 
0x000000c0014de218:  0x0000000000000040  0x0000000000000000 
0x000000c0014de228:  0x000000c0014de278  0x0000000000000001 
0x000000c0014de238:  0x000000021dc7b378  0x0000000000000038 
0x000000c0014de248:  0x000000c00151d1a0 !0x000000c0014de278 
0x000000c0014de258: >0x000000c0003728c0  0x000000c030067180 
0x000000c0014de268:  0x00000000007272c0  0x000000c02eaf0d00 
0x000000c0014de278:  0x0000000000000000  0x0000000000000000 
0x000000c0014de288:  0x0000000000000040  0x000000c0003728c0 
0x000000c0014de298:  0x000000c030067180  0x000000c0014dee18 
0x000000c0014de2a8:  0x00000000005d5c9c <go/types.(*Checker).stmt+0x000000000000245c>  0x000000c0003728c0 
0x000000c0014de2b8:  0x0000000000000003  0x00000000007272c0 
0x000000c0014de2c8:  0x000000c02eaf0d00  0x0000000000000000 
0x000000c0014de2d8:  0x0000000000000000  0x000000c0010e0300 
0x000000c0014de2e8:  0x0000000000413465 <runtime.typedmemmove+0x0000000000000065>  0x000000c0010e0328 
0x000000c0014de2f8:  0x0000000000403976 <runtime.interhash+0x0000000000000056>  0x00000000005c3e10 <go/types.(*operand).assignableTo+0x00000000000000d0> 
0x000000c0014de308:  0x0000000000726c58  0x000000000088c340 
0x000000c0014de318:  0x0000000000726c58  0x000000000088c340 
0x000000c0014de328:  0x000000c0010e0368  0x000000000040e38b <runtime.mapaccess2+0x000000000000006b> 
0x000000c0014de338:  0x000000c0010e03d0  0xa30000000088c340 
0x000000c0014de348:  0x0800000000000000  0x0000000000726c58 
runtime.sigpanic()
    /tmp/workdir/go/src/runtime/signal_unix.go:830 +0x305 fp=0xc0014de258 sp=0xc0014de208 pc=0x449e85
created by golang.org/x/tools/go/packages.(*loader).loadRecursive.func1
    /tmp/workdir/gopath/src/golang.org/x/tools/go/packages/packages.go:832 +0x8f

greplogs --dashboard -md -l -e '(?ms)\Aopenbsd-.*unexpected return pc for runtime\.sigpanic' --since=2022-02-01

2022-04-22T01:41:25-5d7ca8a-be1d738/openbsd-amd64-68 2022-03-18T12:07:27-12eca21/openbsd-386-68

[bcmills]

This may be related to #52043 (attn @cherrymui; CC @golang/runtime).