tests := [...]TestCase{
		{
			name: "chan recv",
			f:    blockChanRecv,
			stk: []string{
				"runtime.chanrecv1",
				"runtime/pprof.blockChanRecv",
				"runtime/pprof.TestBlockProfile",
			},
			re: `
[0-9]+ [0-9]+ @( 0x[[:xdigit:]]+)+
#	0x[0-9a-f]+	runtime\.chanrecv1\+0x[0-9a-f]+	.*runtime/chan.go:[0-9]+
#	0x[0-9a-f]+	runtime/pprof\.blockChanRecv\+0x[0-9a-f]+	.*runtime/pprof/pprof_test.go:[0-9]+