Only build LLVM tools Rust needs.

Author: vadimcn

Makefile.in

@@ -371,6 +371,9 @@ DRIVER_CRATE := $(S)src/driver/driver.rs
 LLVM_COMPONENTS=x86 arm mips ipo bitreader bitwriter linker asmparser jit mcjit \
                 interpreter instrumentation
 
+# Only build these LLVM tools
+LLVM_TOOLS=bugpoint llc llvm-ar llvm-as llvm-dis llvm-mc opt
+
 define DEF_LLVM_VARS
 # The configure script defines these variables with the target triples
 # separated by Z. This defines new ones with the expected format.

mk/llvm.mk

@@ -28,7 +28,7 @@ LLVM_STAMP_$(1) = $$(CFG_LLVM_BUILD_DIR_$(1))/llvm-auto-clean-stamp
 
 $$(LLVM_CONFIG_$(1)): $$(LLVM_DEPS) $$(LLVM_STAMP_$(1))
 	@$$(call E, make: llvm)
-	$$(Q)$$(MAKE) -C $$(CFG_LLVM_BUILD_DIR_$(1)) $$(CFG_LLVM_BUILD_ENV_$(1))
+	$$(Q)$$(MAKE) -C $$(CFG_LLVM_BUILD_DIR_$(1)) $$(CFG_LLVM_BUILD_ENV_$(1)) ONLY_TOOLS="$$(LLVM_TOOLS)"
 	$$(Q)touch $$(LLVM_CONFIG_$(1))
 endif