build:
mkdir $@
+ifneq ($(DEB_HOST_GNU_TYPE),$(DEB_BUILD_GNU_TYPE))
+
+LLVM_CROSS_FLAGS += -DCMAKE_C_COMPILER=$(DEB_HOST_GNU_TYPE)-gcc
+LLVM_CROSS_FLAGS += -DCMAKE_CXX_COMPILER=$(DEB_HOST_GNU_TYPE)-g++
+LLVM_CROSS_FLAGS += -DCMAKE_SYSTEM_PROCESSOR=$(DEB_HOST_GNU_CPU)
+
+LLVM_CROSS_FLAGS += -DCMAKE_CROSSCOMPILING=True
+## We don't need host tablegens, because we use qemu & binfmt to run
+## arm64 binaries on x86
+# LLVM_CROSS_FLAGS += -DLLVM_TABLEGEN="<path-to-host-bin>/llvm-tblgen"
+# LLVM_CROSS_FLAGS += -DCLANG_TABLEGEN="<path-to-host-bin>/clang-tblgen"
+LLVM_CROSS_FLAGS += -DLLVM_DEFAULT_TARGET_TRIPLE=$(DEB_HOST_GNU_TYPE)
+LLVM_CROSS_FLAGS += -DLLVM_TARGET_ARCH=$(DEB_TARGET_GNU_CPU)
+#LLVM_CROSS_FLAGS += -DLLVM_TARGETS_TO_BUILD=$(shell echo $(DEB_HOST_ARCH)|tr '[:lower:]' '[:upper:]')
+endif
+
+
build/build.ninja: build llvm/tools/clang llvm/projects/openmp
- cd $(@D) && cmake -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_INSTALL_PREFIX="$(PREFIX)" -DLLVM_ENABLE_ASSERTIONS=ON -DLLVM_ENABLE_BACKTRACES=ON -DLLVM_ENABLE_WERROR=OFF -DBUILD_SHARED_LIBS=OFF -DLLVM_ENABLE_RTTI=ON -G "Ninja" $(CURDIR)/llvm
+# printenv | sort
+ cd $(@D) && cmake -DCMAKE_BUILD_TYPE=RelWithDebInfo -DCMAKE_INSTALL_PREFIX="$(PREFIX)" \
+ -DLLVM_ENABLE_ASSERTIONS=ON -DLLVM_ENABLE_BACKTRACES=ON -DLLVM_ENABLE_WERROR=OFF \
+ -DBUILD_SHARED_LIBS=OFF -DLLVM_ENABLE_RTTI=ON $(LLVM_CROSS_FLAGS) \
+ -G "Ninja" $(CURDIR)/llvm
+
install: all
cd build && ninja install