cmd/compile/internal/types2: TestStdlib failures

[gopherbot]

#!watchflakes
default <- pkg == "cmd/compile/internal/types2" && test == "TestStdlib"

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestStdlib
package fipsdeps
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/crypto/internal/fips140deps/fipsdeps.go
package main
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/cmd/objdump/main.go
package unsafeheader
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/unsafeheader/unsafeheader.go
package calloc
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/coverage/calloc/batchcounteralloc.go
package cacheprog
...
  cmd/compile/internal/types2_test.TestStdlib()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/cmd/compile/internal/types2/stdlib_test.go:66 +0x433
  testing.tRunner()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2036 +0x21c
  testing.(*T).Run.gowrap1()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2101 +0x38
==================
680 packages typechecked in 19.076955087s
    testing.go:1712: race detected during execution of test
--- FAIL: TestStdlib (22.50s)

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "cmd/compile/internal/types2" && test == "TestStdlib"

2025-12-09 16:51 gotip-linux-amd64-longtest-race go@1274d58d cmd/compile/internal/types2.TestStdlib (log)

=== RUN   TestStdlib
package fipsdeps
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/crypto/internal/fips140deps/fipsdeps.go
package main
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/cmd/objdump/main.go
package unsafeheader
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/unsafeheader/unsafeheader.go
package calloc
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/coverage/calloc/batchcounteralloc.go
package cacheprog
...
  cmd/compile/internal/types2_test.TestStdlib()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/cmd/compile/internal/types2/stdlib_test.go:66 +0x433
  testing.tRunner()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2036 +0x21c
  testing.(*T).Run.gowrap1()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2101 +0x38
==================
680 packages typechecked in 19.076955087s
    testing.go:1712: race detected during execution of test
--- FAIL: TestStdlib (22.50s)

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "cmd/compile/internal/types2" && test == "TestStdlib"

2025-12-10 21:47 gotip-linux-amd64-longtest-race go@b2a697bd cmd/compile/internal/types2.TestStdlib (log)

=== RUN   TestStdlib
package atomic
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/atomic/atomic_amd64.go
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/atomic/doc.go
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/atomic/stubs.go
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/atomic/types.go
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/atomic/types_64bit.go
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/atomic/unaligned.go
	 /home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/atomic/xchg8.go
package goarch
...
  cmd/compile/internal/types2_test.TestStdlib()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/cmd/compile/internal/types2/stdlib_test.go:66 +0x433
  testing.tRunner()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2036 +0x21c
  testing.(*T).Run.gowrap1()
      /home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2101 +0x38
==================
680 packages typechecked in 20.586333875s
    testing.go:1712: race detected during execution of test
--- FAIL: TestStdlib (25.49s)

— watchflakes

[linsite]

I think this is introduced by https://go-review.googlesource.com/c/go/+/726580, and fixed by https://go-review.googlesource.com/c/go/+/729041.

@mrkfrmn