smallvectors unit test fails in C++03 mode

Submitted by Christoph Hertzberg @chhtz

Assigned to Nobody

Link to original bugzilla bug (#1711)
Version: 3.4 (development)

Description

As noted in Bug #1692 (closed) comment 5, smallvectors fails in C++03 mode since these commits (in default and 3.3):
cf7e2e27
441b3511

Perhaps we can let is_valid_index_type check explicitly for common non-integral types like float/double/complex<*>.
Or we just disable the test in C++03 mode.

Blocking

#1608