The get_custom_property method of the PolyLineT class comes in the two following variants:

  typedef void* CustomPropertyHandle;

  // property access by handle  (byte-wise)
  void get_custom_property(CustomPropertyHandle _property_handle, unsigned int _vertex, void* _dst) const;

  // property access by name (byte-wise),  (slower than by handle)
  void get_custom_property(const std::string& _name, unsigned int _vertex, void* _dst) const;

Note that the CustomPropertyHandle is defined as void*. This causes a call to get_custom_property("foo", ....) to be handled with the first variant. My guess is that the "foo" literal is in this case interpreted as a char array and implicitely casted to void* with higher precedence than std::string. I claim that this is undesired behavior and ask to investigate alternative solutions. The same problem should apply for related methods set_custom_property, custom_property_available and release_custom_property.

The problem was observed with the Microsoft Visual Studio 2013 compiler.