warning: reference to local variable ‘rhs’ returned

[micwoj92]

Using gcc 13.2.1

[ 50%] Building CXX object CMakeFiles/lightmaputil.dir/src/LightmapUtil.cpp.o
In file included from /home/micwoj92/LightmapUtil/src/LightmapUtil.h:4,
                 from /home/micwoj92/LightmapUtil/src/LightmapUtil.cpp:10:
/home/micwoj92/LightmapUtil/src/bsplib.h: In member function ‘dvertex_t& dvertex_t::operator+(dvertex_t)’:
/home/micwoj92/LightmapUtil/src/bsplib.h:367:24: warning: reference to local variable ‘rhs’ returned [-Wreturn-local-addr]
  367 |                 return rhs;
      |                        ^~~
/home/micwoj92/LightmapUtil/src/bsplib.h:362:40: note: declared here
  362 |         dvertex_t& operator+(dvertex_t rhs)
      |                              ~~~~~~~~~~^~~
/home/micwoj92/LightmapUtil/src/bsplib.h: In member function ‘dvertex_t& dvertex_t::operator-(dvertex_t)’:
/home/micwoj92/LightmapUtil/src/bsplib.h:374:24: warning: reference to local variable ‘rhs’ returned [-Wreturn-local-addr]
  374 |                 return rhs;
      |                        ^~~
/home/micwoj92/LightmapUtil/src/bsplib.h:369:40: note: declared here
  369 |         dvertex_t& operator-(dvertex_t rhs)
      |                              ~~~~~~~~~~^~~

Using clang 16.0.6 this code also generates warning:

[ 50%] Building CXX object CMakeFiles/lightmaputil.dir/src/LightmapUtil.cpp.o
In file included from /home/micwoj92/LightmapUtil/src/LightmapUtil.cpp:10:
In file included from /home/micwoj92/LightmapUtil/src/LightmapUtil.h:4:
/home/micwoj92/LightmapUtil/src/bsplib.h:367:10: warning: reference to stack memory associated with parameter 'rhs' returned [-Wreturn-stack-address]
                return rhs;
                       ^~~
/home/micwoj92/LightmapUtil/src/bsplib.h:374:10: warning: reference to stack memory associated with parameter 'rhs' returned [-Wreturn-stack-address]
                return rhs;
                       ^~~
2 warnings generated.

[treacherousfiend]

i hate these operators so much, originally they didn't work on MSVC so i fixed that and now it causes warnings elsewhere.
expect this to get fixed anywhere between now and never