Test case for #5626

[genotrance]

No description provided.

[Araq]

This only tests that the snippet compiles! @Varriount Don't be as merge happy, please. ;-)

[genotrance]

I've put in a request to revert. However, the test should have been run since all threading test cases should get run by default per this code:

Nim/tests/testament/categories.nim

Lines 200 to 208 in c7cc934

	# ------------------------- threading tests -----------------------------------
	proc threadTests(r: var TResults, cat: Category, options: string) =
	template test(filename: untyped) =
	testSpec r, makeTest(filename, options, cat, actionRun)
	testSpec r, makeTest(filename, options & " -d:release", cat, actionRun)
	testSpec r, makeTest(filename, options & " --tlsEmulation:on", cat, actionRun)
	for t in os.walkFiles("tests/threads/t*.nim"):
	test(t)