cmd/go: TestScript/cover_build_pkg_select failures

[gopherbot]

#!watchflakes
default <- pkg == "cmd/go" && test == "TestScript/cover_build_pkg_select"

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestScript/cover_build_pkg_select
=== PAUSE TestScript/cover_build_pkg_select
=== CONT  TestScript/cover_build_pkg_select
    script_test.go:139: 2025-07-01T20:04:20Z
    script_test.go:141: $WORK=/home/swarming/.swarming/w/ir/x/t/cmd-go-test-136837613/tmpdir1606226136/cover_build_pkg_select2198727550
    script_test.go:163: 
        PATH=/home/swarming/.swarming/w/ir/x/t/cmd-go-test-136837613/tmpdir1606226136/testbin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/cache/tools/bin:/home/swarming/.swarming/w/ir/bbagent_utility_packages:/home/swarming/.swarming/w/ir/bbagent_utility_packages/bin:/home/swarming/.swarming/w/ir/cipd_bin_packages:/home/swarming/.swarming/w/ir/cipd_bin_packages/bin:/home/swarming/.swarming/w/ir/cache/cipd_client:/home/swarming/.swarming/w/ir/cache/cipd_client/bin:/home/swarming/.swarming/cipd_cache/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
        HOME=/no-home
        CCACHE_DISABLE=1
        GOARCH=amd64
...
        fatal error: exit hook invoked panic
        
        goroutine 1 gp=0xc000004380 m=0 mp=0x6c7a40 [running]:
        runtime.throw({0x56ca92?, 0xc000004380?})
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/panic.go:1094 +0x74 fp=0xc00007c8c0 sp=0xc00007c890 pc=0x4cb054
        internal/runtime/exithook.Run.func1()
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/exithook/hooks.go:69 +0x4c fp=0xc00007c8e0 sp=0xc00007c8c0 pc=0x4149ec
        panic({0x55ecc0?, 0xc0000180c0?})
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/panic.go:783 +0x219 fp=0xc00007c990 sp=0xc00007c8e0 pc=0x4cab39
        runtime.goPanicSliceAcap(0x100000686, 0x6e04)
...
        runtime.(*cleanupQueue).dequeue(0x6c6c40)
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mcleanup.go:439 +0x272 fp=0xc000069fa0 sp=0xc000069f68 pc=0x42f332
        runtime.runCleanups()
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mcleanup.go:635 +0x87 fp=0xc000069fe0 sp=0xc000069fa0 pc=0x430127
        runtime.goexit({})
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/asm_amd64.s:1693 +0x1 fp=0xc000069fe8 sp=0xc000069fe0 pc=0x4d3da1
        created by runtime.(*cleanupQueue).createGs in goroutine 1
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mcleanup.go:589 +0x1f7
    script_test.go:163: FAIL: testdata/script/cover_build_pkg_select.txt:46: exec /home/swarming/.swarming/w/ir/x/t/cmd-go-test-136837613/tmpdir1606226136/cover_build_pkg_select2198727550/modex.exe: exit status 2
--- FAIL: TestScript/cover_build_pkg_select (7.31s)

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "cmd/go" && test == "TestScript/cover_build_pkg_select"

2025-06-30 17:44 go1.25-linux-amd64-longtest release-branch.go1.25@9ae38be3 cmd/go.TestScript/cover_build_pkg_select (log)

=== RUN   TestScript/cover_build_pkg_select
=== PAUSE TestScript/cover_build_pkg_select
=== CONT  TestScript/cover_build_pkg_select
    script_test.go:139: 2025-07-01T20:04:20Z
    script_test.go:141: $WORK=/home/swarming/.swarming/w/ir/x/t/cmd-go-test-136837613/tmpdir1606226136/cover_build_pkg_select2198727550
    script_test.go:163: 
        PATH=/home/swarming/.swarming/w/ir/x/t/cmd-go-test-136837613/tmpdir1606226136/testbin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/x/w/goroot/bin:/home/swarming/.swarming/w/ir/cache/tools/bin:/home/swarming/.swarming/w/ir/bbagent_utility_packages:/home/swarming/.swarming/w/ir/bbagent_utility_packages/bin:/home/swarming/.swarming/w/ir/cipd_bin_packages:/home/swarming/.swarming/w/ir/cipd_bin_packages/bin:/home/swarming/.swarming/w/ir/cache/cipd_client:/home/swarming/.swarming/w/ir/cache/cipd_client/bin:/home/swarming/.swarming/cipd_cache/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
        HOME=/no-home
        CCACHE_DISABLE=1
        GOARCH=amd64
...
        fatal error: exit hook invoked panic
        
        goroutine 1 gp=0xc000004380 m=0 mp=0x6c7a40 [running]:
        runtime.throw({0x56ca92?, 0xc000004380?})
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/panic.go:1094 +0x74 fp=0xc00007c8c0 sp=0xc00007c890 pc=0x4cb054
        internal/runtime/exithook.Run.func1()
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/internal/runtime/exithook/hooks.go:69 +0x4c fp=0xc00007c8e0 sp=0xc00007c8c0 pc=0x4149ec
        panic({0x55ecc0?, 0xc0000180c0?})
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/panic.go:783 +0x219 fp=0xc00007c990 sp=0xc00007c8e0 pc=0x4cab39
        runtime.goPanicSliceAcap(0x100000686, 0x6e04)
...
        runtime.(*cleanupQueue).dequeue(0x6c6c40)
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mcleanup.go:439 +0x272 fp=0xc000069fa0 sp=0xc000069f68 pc=0x42f332
        runtime.runCleanups()
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mcleanup.go:635 +0x87 fp=0xc000069fe0 sp=0xc000069fa0 pc=0x430127
        runtime.goexit({})
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/asm_amd64.s:1693 +0x1 fp=0xc000069fe8 sp=0xc000069fe0 pc=0x4d3da1
        created by runtime.(*cleanupQueue).createGs in goroutine 1
        	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mcleanup.go:589 +0x1f7
    script_test.go:163: FAIL: testdata/script/cover_build_pkg_select.txt:46: exec /home/swarming/.swarming/w/ir/x/t/cmd-go-test-136837613/tmpdir1606226136/cover_build_pkg_select2198727550/modex.exe: exit status 2
--- FAIL: TestScript/cover_build_pkg_select (7.31s)

— watchflakes