Based on just what you posted I'd say that something must be up with your tool-chain; but that's really just guessing.
The code snippet looks sane enough (old-school but sane).
Does the same thing happen if you use modern C++ - like:
for (auto& point : points) { ... }
?
Could you provide a comple, minimal, compilable example so other people can try to replicate your results?
Also, more details on OS and tool-chain would be good.