internal/godebugs: tests exceed package test timeout of 6 minutes

[gopherbot]

#!watchflakes
default <- pkg == "internal/godebugs" && `test timed out after 6m0s`

Issue created automatically to collect these failures.

Example (log):

=== RUN   TestAll
panic: test timed out after 6m0s
	running tests:
		TestAll (6m0s)

goroutine 34 gp=0x10c000211408 m=7 mp=0x10c00018c008 [running]:
panic({0x799b40?, 0x10c00002c140?})
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/panic.go:879 +0x16f fp=0x10c00008ff10 sp=0x10c00008fe60 pc=0x5642cf
testing.(*M).startAlarm.func1()
	/home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2802 +0x739 fp=0x10c00008ffe0 sp=0x10c00008ff10 pc=0x6a09d9
...
runtime.gopark(0x7c9f2c2b4c?, 0x1?, 0xcc?, 0xab?, 0x0?)
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/proc.go:462 +0xce fp=0x10c000353740 sp=0x10c000353720 pc=0x5647ee
runtime.gcBgMarkWorker(0x10c00034a000)
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mgc.go:1791 +0xeb fp=0x10c0003537c8 sp=0x10c000353740 pc=0x50adab
runtime.gcBgMarkStartWorkers.gowrap1()
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mgc.go:1695 +0x17 fp=0x10c0003537e0 sp=0x10c0003537c8 pc=0x50ac97
runtime.goexit({})
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/asm_amd64.s:1771 +0x1 fp=0x10c0003537e8 sp=0x10c0003537e0 pc=0x56b8c1
created by runtime.gcBgMarkStartWorkers in goroutine 7
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mgc.go:1695 +0x105

— watchflakes

[gopherbot]

Found new dashboard test flakes for:

#!watchflakes
default <- pkg == "internal/godebugs" && test == "TestAll"

2026-03-26 19:44 go1.26-linux-amd64-asan-clang15 release-branch.go1.26@4ef27877 internal/godebugs.TestAll [SKIP] (log)

=== RUN   TestAll
panic: test timed out after 6m0s
	running tests:
		TestAll (6m0s)

goroutine 34 gp=0x10c000211408 m=7 mp=0x10c00018c008 [running]:
panic({0x799b40?, 0x10c00002c140?})
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/panic.go:879 +0x16f fp=0x10c00008ff10 sp=0x10c00008fe60 pc=0x5642cf
testing.(*M).startAlarm.func1()
	/home/swarming/.swarming/w/ir/x/w/goroot/src/testing/testing.go:2802 +0x739 fp=0x10c00008ffe0 sp=0x10c00008ff10 pc=0x6a09d9
...
runtime.gopark(0x7c9f2c2b4c?, 0x1?, 0xcc?, 0xab?, 0x0?)
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/proc.go:462 +0xce fp=0x10c000353740 sp=0x10c000353720 pc=0x5647ee
runtime.gcBgMarkWorker(0x10c00034a000)
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mgc.go:1791 +0xeb fp=0x10c0003537c8 sp=0x10c000353740 pc=0x50adab
runtime.gcBgMarkStartWorkers.gowrap1()
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mgc.go:1695 +0x17 fp=0x10c0003537e0 sp=0x10c0003537c8 pc=0x50ac97
runtime.goexit({})
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/asm_amd64.s:1771 +0x1 fp=0x10c0003537e8 sp=0x10c0003537e0 pc=0x56b8c1
created by runtime.gcBgMarkStartWorkers in goroutine 7
	/home/swarming/.swarming/w/ir/x/w/goroot/src/runtime/mgc.go:1695 +0x105

— watchflakes

[dmitshur]

It looks like the internal/godebugs package tests often come quite close to the 6 minute timeout, e.g., past runs have taken 325.885s and similar. And in this case it went over the time limit, causing this failure.

go test -count=1 internal/godebugs takes around 5 seconds locally. Perhaps something about it takes much longer on the -asan builder specifically.

CC @golang/compiler.

[randall77]

Maybe we should skip except on the longtest builder?
We might need a longtest asan builder.