Add checks for compiler flags instead of just blindly trying to use them.
Add checks for compiler flags instead of just blindly trying to use them.

Change-Id: I57f297b893125cc5935f98badbcaa733116916ed

aashish24/VTK-old,ashray/VTK-EVM,biddisco/VTK,aashish24/VTK-old,biddisco/VTK,biddisco/VTK,biddisco/VTK,demarle/VTK,daviddoria/PointGraphsPhase1,demarle/VTK,sumedhasingla/VTK,johnkit/vtk-dev,berendkleinhaneveld/VTK,daviddoria/PointGraphsPhase1,SimVascular/VTK,biddisco/VTK,hendradarwin/VTK,sumedhasingla/VTK,cjh1/VTK,ashray/VTK-EVM,daviddoria/PointGraphsPhase1,cjh1/VTK,daviddoria/PointGraphsPhase1,msmolens/VTK,johnkit/vtk-dev,sankhesh/VTK,ashray/VTK-EVM,spthaolt/VTK,candy7393/VTK,gram526/VTK,demarle/VTK,mspark93/VTK,ashray/VTK-EVM,demarle/VTK,sumedhasingla/VTK,mspark93/VTK,jmerkow/VTK,berendkleinhaneveld/VTK,berendkleinhaneveld/VTK,sumedhasingla/VTK,cjh1/VTK,hendradarwin/VTK,gram526/VTK,mspark93/VTK,spthaolt/VTK,SimVascular/VTK,spthaolt/VTK,sumedhasingla/VTK,aashish24/VTK-old,johnkit/vtk-dev,collects/VTK,keithroe/vtkoptix,collects/VTK,collects/VTK,mspark93/VTK,johnkit/vtk-dev,SimVascular/VTK,daviddoria/PointGraphsPhase1,keithroe/vtkoptix,demarle/VTK,spthaolt/VTK,biddisco/VTK,ashray/VTK-EVM,ashray/VTK-EVM,candy7393/VTK,biddisco/VTK,candy7393/VTK,sankhesh/VTK,SimVascular/VTK,candy7393/VTK,mspark93/VTK,sumedhasingla/VTK,johnkit/vtk-dev,sankhesh/VTK,demarle/VTK,SimVascular/VTK,msmolens/VTK,jmerkow/VTK,keithroe/vtkoptix,candy7393/VTK,msmolens/VTK,berendkleinhaneveld/VTK,cjh1/VTK,msmolens/VTK,sankhesh/VTK,msmolens/VTK,keithroe/vtkoptix,johnkit/vtk-dev,msmolens/VTK,cjh1/VTK,hendradarwin/VTK,collects/VTK,aashish24/VTK-old,sumedhasingla/VTK,jmerkow/VTK,jmerkow/VTK,SimVascular/VTK,sankhesh/VTK,aashish24/VTK-old,collects/VTK,mspark93/VTK,daviddoria/PointGraphsPhase1,candy7393/VTK,ashray/VTK-EVM,jmerkow/VTK,aashish24/VTK-old,demarle/VTK,hendradarwin/VTK,spthaolt/VTK,collects/VTK,hendradarwin/VTK,cjh1/VTK,spthaolt/VTK,gram526/VTK,keithroe/vtkoptix,mspark93/VTK,mspark93/VTK,candy7393/VTK,jmerkow/VTK,hendradarwin/VTK,msmolens/VTK,sankhesh/VTK,jmerkow/VTK,sankhesh/VTK,candy7393/VTK,berendkleinhaneveld/VTK,gram526/VTK,keithroe/vtkoptix,demarle/VTK,gram526/VTK,keithroe/vtkoptix,SimVascular/VTK,msmolens/VTK,gram526/VTK,jmerkow/VTK,berendkleinhaneveld/VTK,sumedhasingla/VTK,keithroe/vtkoptix,gram526/VTK,gram526/VTK,berendkleinhaneveld/VTK,johnkit/vtk-dev,spthaolt/VTK,hendradarwin/VTK,sankhesh/VTK,SimVascular/VTK,ashray/VTK-EVM