CMake: Add option to enable -Werror cflag in some areas

It is rather annoying attitude nowadays to use const qualifier all over the
place, including using it for multi-dimensional arrays. This isn't really
supported in GCC prior to version 5.0 because it considers such an arrays
to be a "pointer to a const pointer" which gives implicit casting errors.

It's not possible to disable this particular type of warnings treated as
errors in any GCC version prior to 5.0 as well, meaning currently usage of
-Werror globally in Blender code is not possible at all.

This commit makes it possible to use -Werror in areas which are complaint
with older GCC versions. New advanced CMake options are:

- WITH_COMPOSITOR_WERROR
- WITH_LIBMV_WERROR
- WITH_CYCLES_WERROR

1 files changed, 16 insertions, 8 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index e214b23a5db..88cf5b73da6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -221,7 +221,11 @@ mark_as_advanced(WITH_SYSTEM_BULLET)
 option(WITH_GAMEENGINE    "Enable Game Engine" ${_init_GAMEENGINE})
 option(WITH_PLAYER        "Build Player" OFF)
 option(WITH_OPENCOLORIO   "Enable OpenColorIO color management" ${_init_OPENCOLORIO})
-option(WITH_COMPOSITOR    "Enable the tile based nodal compositor" ON)
+
+# Compositor
+option(WITH_COMPOSITOR         "Enable the tile based nodal compositor" ON)
+option(WITH_COMPOSITOR_WERROR  "Treat warnings as errors in compositor code" OFF)
+mark_as_advanced(WITH_COMPOSITOR_WERROR)
 
 # GHOST Windowing Library Options
 option(WITH_GHOST_DEBUG   "Enable debugging output for the GHOST library" OFF)
@@ -318,9 +322,11 @@ if(UNIX AND NOT APPLE)
 endif()
 
 # Camera/motion tracking
-option(WITH_LIBMV         "Enable libmv structure from motion library" ON)
+option(WITH_LIBMV         "Enable Libmv structure from motion library" ON)
 option(WITH_LIBMV_SCHUR_SPECIALIZATIONS "Enable fixed-size schur specializations." ${_init_LIBMV_SCHUR_SPECIALIZATION})
+option(WITH_LIBMV_WERROR  "Treat warnings as errors in Libmv (and Blender's motion tracking) code")
 mark_as_advanced(WITH_LIBMV_SCHUR_SPECIALIZATIONS)
+mark_as_advanced(WITH_LIBMV_WERROR)
 
 # Freestyle
 option(WITH_FREESTYLE     "Enable Freestyle (advanced edges rendering)" ON)
@@ -354,18 +360,20 @@ if(UNIX AND NOT APPLE)
 endif()
 
 # Cycles
-option(WITH_CYCLES					"Enable cycles Render Engine" ON)
-option(WITH_CYCLES_STANDALONE		"Build cycles standalone application" OFF)
-option(WITH_CYCLES_STANDALONE_GUI	"Build cycles standalone with GUI" OFF)
+option(WITH_CYCLES					"Enable Cycles Render Engine" ON)
+option(WITH_CYCLES_STANDALONE		"Build Cycles standalone application" OFF)
+option(WITH_CYCLES_STANDALONE_GUI	"Build Cycles standalone with GUI" OFF)
 option(WITH_CYCLES_OSL				"Build Cycles with OSL support" ${_init_CYCLES_OSL})
-option(WITH_CYCLES_CUDA_BINARIES	"Build cycles CUDA binaries" OFF)
+option(WITH_CYCLES_CUDA_BINARIES	"Build Cycles CUDA binaries" OFF)
 set(CYCLES_CUDA_BINARIES_ARCH sm_20 sm_21 sm_30 sm_35 sm_50 sm_52 CACHE STRING "CUDA architectures to build binaries for")
 mark_as_advanced(CYCLES_CUDA_BINARIES_ARCH)
 unset(PLATFORM_DEFAULT)
-option(WITH_CYCLES_LOGGING	"Build cycles with logging support" ON)
-option(WITH_CYCLES_DEBUG	"Build cycles with extra debug capabilities" OFF)
+option(WITH_CYCLES_LOGGING	"Build Cycles with logging support" ON)
+option(WITH_CYCLES_DEBUG	"Build Cycles with extra debug capabilities" OFF)
+option(WITH_CYCLES_WERROR	"Treat warnings as errors in Cycles code" OFF)
 mark_as_advanced(WITH_CYCLES_LOGGING)
 mark_as_advanced(WITH_CYCLES_DEBUG)
+mark_as_advanced(WITH_CYCLES_WERROR)
 
 # LLVM
 option(WITH_LLVM					"Use LLVM" OFF)