roscpp: Fix clashing namespaces for ros::param::set

[smits]

Compiling on RHEL with gcc 4.4.6 resulted in the following error:

/usr/lib/gcc/x86_64-redhat-linux/4.4.6/../../../../include/c++/4.4.6/bits/stl_set.h: In function 'void ros::param::setImpl(const std::string&, const std::vector<T, std::allocator<_CharT> >&)':
/usr/lib/gcc/x86_64-redhat-linux/4.4.6/../../../../include/c++/4.4.6/bits/stl_set.h:87: error: 'template<class _Key, class _Compare, class _Alloc> class std::set' is not a function,
/home/codac-dev/rpmbuild/BUILD/ros-hydro-core-1.9.50/src/roscpp/include/ros/param.h:161: error:   conflict with 'void ros::param::set(const std::string&, const std::map<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, bool, std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, bool> > >&)'

Apparently the set was clashing with std::set for some reason.

Signed-off-by: Ruben Smits ruben.smits@intermodalics.eu

[dirk-thomas]

Can you please clarify what exactly you are compiling and how? Is it just ros_comm or also any custom code?

It seems that the invocation of set() (https://github.com/smits/ros_comm/blob/9c133c6a761f73accbe674af9df1f64c0db49051/clients/roscpp/src/libros/param.cpp#L127) is ambiguous when compiling param.cpp. This would make sense if any code before would define using namespace std but since it is happening in a cpp file rather than a header (and ROS does not use using namespace in headers) I don't know where that should be coming from.

[smits]

I was compiling the ROS Hydro Bare flavour from source in a catkin workspace on ...

lsb_release -a
LSB Version:    :core-4.0-amd64:core-4.0-noarch:graphics-4.0-amd64:graphics-4.0-noarch:printing-4.0-amd64:printing-4.0-noarch
Distributor ID: RedHatEnterpriseWorkstation
Description:    Red Hat Enterprise Linux Workstation release 6.3 (Santiago)
Release:    6.3
Codename:   Santiago

using

gcc --version
gcc (GCC) 4.4.6 20120305 (Red Hat 4.4.6-4)

[dirk-thomas]

I can reproduce the issue under Ubuntu Quantal when using gcc-4.4.