assert(0x_cafei == complex(0, 0xcafe))

	// octals
	assert(0o_1 == 01)
	assert(0o12 == 012)
	assert(0o_1_2 == 012)
	assert(0o_1_2i == complex(0, 0o12))

	// binaries
	assert(0b_1 == 1)
	assert(0b10 == 2)
	assert(0b_1_0 == 2)
	assert(0b_1_0i == complex(0, 2))

	// decimal floats
	assert(0. == 0.0)
	assert(.0 == 0.0)
	assert(1_0. == 10.0)
	assert(.0_1 == 0.01)
	assert(1_0.0_1 == 10.01)

	if pp != nil {
		// Overflow records in profBuf have all header values set to zero. Make
		// sure that real headers have at least one bit set.
		hdr[0] = uint64(pp.id)<<1 | 0b1
	} else {
		hdr[0] = 0b10
	}
	if gp != nil {
		hdr[1] = gp.goid
	}
	hdr[2] = uint64(mp.procid)

	// Allow only one writer at a time
	for !trace.signalLock.CompareAndSwap(0, 1) {