- Disclaimer: This is all experimental forward-looking stuff, we don't recommend using this yet!
- Added native support for Clang command-line on Windows ('clang-cl' is not required, but still supported)
- Clang debug symbols are now Visual Studio compatible (use latest Clang 3.6.0 prelease build.)
- Clang linker (LLD.exe) now works with most UE4 binaries, but debug symbols won't work
- New 'WindowsPlatform.bUseVCCompilerArgs' that controls whether to the VC-style wrapper with Clang
- Implemented precompiled header support (requires native Clang binary.) There are still a few bugs in Clang with struct packing which prevent us from using PCHs on Windows though.
- Editor still can't compile under Clang because of some DX header file issues, possibly system include related.
- Unreal Build Tool: Reduced default performance spew when using the local executor (non-XGE builds.)
[CL 2393051 by Mike Fricker in Main branch]
- Changed formatting of some console output
- No longer print notification about full C++ rescan unless that feature is active
[CL 2264360 by Mike Fricker in Main branch]
UnrealBuildTool 'Makefiles' allow for very fast iterative builds.
- New BuildConfiguration.xml setting added: "bUseExperimentalFastBuildIteration" (disabled by default)
- Turning this on causes Unreal Build Tool to emit 'UBT Makefiles' for targets when they're built the first time.
- Subsequent builds will load these Makefiles and begin outdatedness checking and build invocation very quickly.
- The caveat is that if source files are added or removed to the project, UBT will need to gather information about those in order for your build to complete successfully.
- Currently, you must run the project file generator after adding/removing source files to tell UBT to re-gather this information.
- Events that can invalidate the 'UBT Makefile':
- Adding/removing .cpp files
- Adding/removing .h files with UObjects
- Adding new UObject types to a file that didn't previously have any
- Changing global build settings (most settings in this file qualify.)
- Changed code that affects how Unreal Header Tool works
- You can force regeneration of the 'UBT Makefile' by passing the '-Gather' argument, or simply regenerating project files
- New command-line parameters added:
- "-Gather": Tells UBT to always perform the gather step (slower but will catch project structural changes)
- "-NoGather": Disables the gather step, unless UBT detects that it must be done. This is the default when bUseExperimentalFastBuildIteration is enabled
- "-GatherOnly": Runs the gather step and saves a UBTMakefile, but doesn't build anything
- "-Assemble": Tells UBT to also assemble build products. This always defaults to enabled
- "-NoAssemble": Tells UBT to skip the assemble step, whether we gathered build products or not
- "-AssembleOnly": Tells UBT to only assemble build products and not to gather, unless UBT determines it must
Other changes:
- UBT now keeps track of which targets it was building in an intermediate file, to help it invalidate cached includes in subsequent runs when the targets are different
- C++ includes are now stored in a class separate from the C++ compile enviroment (for easier serialization)
- The method that UBT uses to find the CoreUObject module timestamp was rewritten
- Various '@todo ubtmake' comments added to tag possible remaining Makefile tasks
- The 'FileItem' class had some member variable comments and code cleaned up, while making it serializable
- Cleaned up the comments and member variables in the "Action" class, while making it serializable
- Some UBT classes are now "serializable". This is because we need to store the data in UBTMakefiles.
- Removed support for Actions to tinker with Stdout and Stderror (was not used for anything)
- Moved PrecompileHeaderEnvironment class to the UEBuildModule.cs source file
- Plugin intermediate include directories are now selected on demand rather than cached early
- Toolchain code for gathering prerequisite headers is now shared in a single function (AddPrerequisiteSourceFile)
- Removed Action.StatusDetailedDescription, was not used for anything
- Removed UEBuildConfiguration.bExcludePlugins, was not used for anything
- Removed ECompilationResult.FailedDueToHeaderChange, was not used for anything
[CL 2254472 by Mike Fricker in Main branch]
By either manually configuring distcc & DMUCS as per their documentation, or using the DistCode Xcode plugin compilation can be distributed amongst networked Macs.
All Macs must have the same developer tools installed & the same distcc/DMUCS/DistCode and be on the same local network.
This works for compiling for Mac & iOS and it should be possible to configure distcc & DMUCS manually for use on build farms for remote building from Windows.
Linux could also use this for local builds or remote build farms - but I'm not in a position to test this.
[CL 2238171 by Mark Satterthwaite in Main branch]