cmd/compile: test/fixedbugs/issue16016.go is flaky on linux-arm64 builder

[cherrymui]

Flaky builder failures start from commit 31ba855. This commit seems not related, so I guess it actually starts one commit earlier, ca4089a, and being lucky on that time.

[cherrymui]

On AMD64:

issue16016.go:13: live at entry to (*T).Foo: vals
issue16016.go:14: live at call to assertE2T2: v
issue16016.go:27: live at call to newobject: autotmp_7
issue16016.go:27: live at call to writebarrierptr: autotmp_7
issue16016.go:32: live at call to newproc: autotmp_7
issue16016.go:29: live at entry to main.func1: q
issue16016.go:30: live at call to newobject: q autotmp_8
issue16016.go:30: live at call to convT2E: q autotmp_8 autotmp_11
issue16016.go:30: live at call to writebarrierptr: q autotmp_8 autotmp_11
issue16016.go:30: live at call to deferproc: autotmp_8
issue16016.go:30: live at call to deferreturn: autotmp_8
<autogenerated>:1: live at entry to (*R).Foo: .this vals
<autogenerated>:2: live at entry to R.Foo: .this vals
<autogenerated>:3: live at entry to Q.Foo: .this .anon0

On ARM64:

issue16016.go:13: live at entry to (*T).Foo: vals
issue16016.go:14: live at call to assertE2T2: v
issue16016.go:27: live at call to newobject: autotmp_7
issue16016.go:27: live at call to writebarrierptr: autotmp_7
issue16016.go:32: live at call to newproc: autotmp_7
issue16016.go:29: live at entry to main.func1: q
issue16016.go:30: live at call to newobject: q autotmp_8
issue16016.go:30: live at call to convT2E: q autotmp_8 autotmp_11
issue16016.go:30: live at call to writebarrierptr: q autotmp_8 autotmp_11
issue16016.go:30: live at call to deferproc: autotmp_8
issue16016.go:30: live at call to deferreturn: autotmp_8
<autogenerated>:1: live at entry to (*R).Foo: .this  // <----- vals is not live here
<autogenerated>:2: live at entry to R.Foo: .this vals
<autogenerated>:3: live at entry to Q.Foo: .this .anon0

[cherrymui]

also happens on mips64: https://build.golang.org/log/d72f4344d7a6b7ebffe87ab8c852bfb8ad6667f7

[gopherbot]

CL https://golang.org/cl/29570 mentions this issue.

[gopherbot]

CL https://golang.org/cl/29652 mentions this issue.