| BUILD_WSI_DIRECTFB_SUPPORT | Linux | `OFF` | Build the loader with the DirectFB entry points enabled. Without this, the DirectFB headers should not be needed, but the extension `VK_EXT_directfb_surface` won't be available. |
| BUILD_WSI_SCREEN_QNX_SUPPORT | QNX | `OFF` | Build the loader with the QNX Screen entry points enabled. Without this the extension `VK_QNX_screen_surface` won't be available. |
| ENABLE_WIN10_ONECORE | Windows | `OFF` | Link the loader to the [OneCore](https://msdn.microsoft.com/en-us/library/windows/desktop/mt654039.aspx) umbrella library, instead of the standard Win32 ones. |
-| USE_CCACHE | Linux | `OFF` | Enable caching with the CCache program. |
| USE_GAS | Linux | `ON` | Controls whether to build assembly files with the GNU assembler, else fallback to C code. |
| USE_MASM | Windows | `ON` | Controls whether to build assembly files with MS assembler, else fallback to C code |
| BUILD_STATIC_LOADER | macOS | `OFF` | This allows the loader to be built as a static library on macOS. Not tested, use at your own risk. |
These variables should be set using the `-D` option when invoking CMake to generate the native platform files.
+### CCACHE
+
+There are 2 methods to enable CCACHE:
+
+1.) Set environment variables
+
+```bash
+# Requires CMake 3.17 (https://cmake.org/cmake/help/latest/envvar/CMAKE_LANG_COMPILER_LAUNCHER.html)
+export CMAKE_CXX_COMPILER_LAUNCHER=/usr/bin/ccache
+export CMAKE_C_COMPILER_LAUNCHER=/usr/bin/ccache
+```
+
+2.) Pass in cache variables
+
+```
+cmake ... -D CMAKE_CXX_COMPILER_LAUNCHER=/usr/bin/ccache -D CMAKE_C_COMPILER_LAUNCHER=/usr/bin/ccache
+```
+
+
+
## Building On Windows
### Windows Development Environment Requirements
cmake --build .
-If your build system supports ccache, you can enable that via CMake option
-`-DUSE_CCACHE=On`
-
### Linux Notes
#### Using The Vulkan Loader Library in this Repository on Linux
add_library(Vulkan::Headers ALIAS vulkan-headers)
endif()
-option(USE_CCACHE "Use ccache" OFF)
-if(USE_CCACHE)
- find_program(CCACHE_FOUND ccache)
- if(CCACHE_FOUND)
- set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE ccache)
- endif()
-endif()
-
include(GNUInstallDirs)
if(UNIX AND NOT APPLE) # i.e.: Linux