diff options
Diffstat (limited to 'Makefile.rules')
-rw-r--r-- | Makefile.rules | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/Makefile.rules b/Makefile.rules index c0ded8e07a..4fb672237e 100644 --- a/Makefile.rules +++ b/Makefile.rules @@ -57,6 +57,54 @@ VPATH=$(PROJ_SRC_DIR) $(UserTargets):: +#------------------------------------------------------------------------ +# LLVMBuild Integration +#------------------------------------------------------------------------ +# +# We use llvm-build to generate all the data required by the Makefile based +# build system in one swoop: +# +# - We generate a file (a Makefile fragment) in the object root which contains +# all the definitions that are required by Makefiles across the entire +# project. +# +# - We generate the library table used by llvm-config. +# +# - We generate the dependencies for the Makefile fragment, so that we will +# automatically reconfigure outselves. + +# The path to the llvm-build tool itself. +LLVMBuildTool := $(PROJ_SRC_ROOT)/utils/llvm-build/llvm-build + +# The files we are going to generate using llvm-build. +LLVMBuildMakeFrag := $(PROJ_OBJ_ROOT)/Makefile.llvmbuild +LLVMConfigLibraryDependenciesInc := \ + $(PROJ_OBJ_ROOT)/tools/llvm-config/LibraryDependencies.inc + +# The rule to create the LLVMBuild Makefile fragment as well as the llvm-config +# library table. +# +# Note that this target gets its real dependencies generated for us by +# llvm-build. +$(LLVMBuildMakeFrag): + $(EchoCmd) Constructing LLVMBuild project information. ; \ + $(LLVMBuildTool) \ + --write-library-table $(LLVMConfigLibraryDependenciesInc) \ + --write-make-fragment $(LLVMBuildMakeFrag) + +# Include the generated Makefile fragment. +# +# We currently only include the dependencies for the fragment itself if we are +# at the top-level. Otherwise, recursive invocations would ends up doing +# substantially more redundant stat'ing. +# +# This means that we won't properly regenerate things for developers used to +# building from a subdirectory, but that is always somewhat unreliable. +ifeq ($(LEVEL),.) +LLVMBUILD_INCLUDE_DEPENDENCIES := 1 +endif +-include $(LLVMBuildMakeFrag) + ################################################################################ # PRECONDITIONS: that which must be built/checked first ################################################################################ |