message: Apply cmake compiler selection into qmake command
  * In particular this means that if you compile with clang, qmake won't
  try to use g++.
diff: @@ -18,7 +18,7 @@ endif()
  # which causes CMake to rerun this target every time so that Qt
  # can do dependency checking and rebuild anything necessary.
  add_custom_command(OUTPUT QRenderDoc
  - COMMAND qmake "CONFIG+=${QMAKE_CONFIG}" "QMAKE_CXXFLAGS+=${warning_flags}" "QMAKE_LFLAGS+=${QMAKE_LDFLAGS}" "DEFINES+=GIT_COMMIT_HASH_LITERAL=${GIT_COMMIT_HASH}" "DESTDIR=${output_dir}" ${CMAKE_CURRENT_SOURCE_DIR}
  + COMMAND qmake "CONFIG+=${QMAKE_CONFIG}" "QMAKE_CC=${CMAKE_C_COMPILER}" "QMAKE_CXX=${CMAKE_CXX_COMPILER}" "QMAKE_LINK=${CMAKE_CXX_COMPILER}" "QMAKE_CXXFLAGS+=${warning_flags}" "QMAKE_LFLAGS+=${QMAKE_LDFLAGS}" "DEFINES+=GIT_COMMIT_HASH_LITERAL=${GIT_COMMIT_HASH}" "DESTDIR=${output_dir}" ${CMAKE_CURRENT_SOURCE_DIR}
  COMMAND MAKEFLAGS= make --no-print-directory)
  add_custom_target(build-qrenderdoc ALL DEPENDS QRenderDoc DEPENDS renderdoc)
  