[Qt-interest] Testing in the project file whether GCC is used as compiler

[Nikos Chantziaras]

I need to append a GCC option in QMAKE_CXXFLAGS, or else the application 
won't run correctly.  That option is only recognized by GCC though, so 
if compiling with another compiler, the build may fail.  Is there a way 
to test this?  Something like:

   gcc {
     QMAKE_CXXFLAGS += -some_gcc_option
   }