Fix C++11 compiling errors and some warnings

[Edward-san]

Hi. I noticed that the c++11 fixes I made in zdoom is not complete in gzdoom, hence I submit two patches: the former should allow the compilation with a C++11 compiler, the latter should shut up these compiler warnings:

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Code: Select all

1:
/home/edward-san/zdoom/gzdoom/trunk/src/gl/data/gl_portaldata.cpp:226:26: warning: 
      suggest braces around initialization of subobject [-Wmissing-braces]
                                FCoverageLine vl = { *v1, *v2 };
                                                     ^~~~~~~~
                                                     {       }

2:
[ 76%] /home/edward-san/zdoom/gzdoom/trunk/src/gl/data/gl_setup.cpp:133:17: warning: 
      comparison of integers of different signs: 'DWORD' (aka 'unsigned int')
      and 'int' [-Wsign-compare]
        for(DWORD i=0;i<numsegs;i++)
                      ~^~~~~~~~
/home/edward-san/zdoom/gzdoom/trunk/src/gl/data/gl_setup.cpp:145:17: warning: 
      comparison of integers of different signs: 'DWORD' (aka 'unsigned int')
      and 'int' [-Wsign-compare]
        for(DWORD i=0;i<numsegs;i++)
                      ~^~~~~~~~

3:
/home/edward-san/zdoom/gzdoom/trunk/src/gl/textures/gl_material.cpp:438:8: warning: 
      variable 'w' is used uninitialized whenever 'if' condition is false
      [-Wsometimes-uninitialized]
                        if (!tex->bHasCanvas)
                            ^~~~~~~~~~~~~~~~
/home/edward-san/zdoom/gzdoom/trunk/src/gl/textures/gl_material.cpp:443:38: note: 
      uninitialized use occurs here
                        if (!hwtex->CreateTexture(buffer, w, h, true, te...
                                                          ^
/home/edward-san/zdoom/gzdoom/trunk/src/gl/textures/gl_material.cpp:438:4: note: 
      remove the 'if' if its condition is always true
                        if (!tex->bHasCanvas)
                        ^~~~~~~~~~~~~~~~~~~~~
/home/edward-san/zdoom/gzdoom/trunk/src/gl/textures/gl_material.cpp:433:9: note: 
      initialize the variable 'w' to silence this warning
                        int w, h;
                             ^
                              = 0
/home/edward-san/zdoom/gzdoom/trunk/src/gl/textures/gl_material.cpp:438:8: warning: 
      variable 'h' is used uninitialized whenever 'if' condition is false
      [-Wsometimes-uninitialized]
                        if (!tex->bHasCanvas)
                            ^~~~~~~~~~~~~~~~
/home/edward-san/zdoom/gzdoom/trunk/src/gl/textures/gl_material.cpp:443:41: note: 
      uninitialized use occurs here
                        if (!hwtex->CreateTexture(buffer, w, h, true, te...
                                                             ^
/home/edward-san/zdoom/gzdoom/trunk/src/gl/textures/gl_material.cpp:438:4: note: 
      remove the 'if' if its condition is always true
                        if (!tex->bHasCanvas)
                        ^~~~~~~~~~~~~~~~~~~~~
/home/edward-san/zdoom/gzdoom/trunk/src/gl/textures/gl_material.cpp:433:12: note: 
      initialize the variable 'h' to silence this warning
                        int w, h;
                                ^
                                 = 0