move this makefile goop up to the top level llvm makefile.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@65544 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/Driver/Makefile b/Driver/Makefile
index 6bcd62e..460c30f 100644
--- a/Driver/Makefile
+++ b/Driver/Makefile
@@ -3,21 +3,14 @@
 CPPFLAGS += -I$(PROJ_SRC_DIR)/../include
 CXXFLAGS = -fno-rtti
 
+# Clang has no plugins, optimize startup time.
+TOOL_NO_EXPORTS = 1
+
 # Include this here so we can get the configuration of the targets
 # that have been configured for construction. We have to do this 
 # early so we can set up LINK_COMPONENTS before including Makefile.rules
 include $(LEVEL)/Makefile.config
 
-# Optimize startup time of the app by not exporting all of the weak symbols
-# from the binary.  This reduces dyld startup time by 4x.
-ifeq ($(OS),Darwin)
-LD.Flags += -Wl,-exported_symbol -Wl,_main
-endif
-
-ifeq ($(OS), $(filter $(OS), Linux NetBSD FreeBSD))
-LD.Flags += -Wl,--version-script=Driver.map
-endif
-
 LINK_COMPONENTS := $(TARGETS_TO_BUILD) bitreader bitwriter codegen ipo selectiondag
 USEDLIBS = clangCodeGen.a clangAnalysis.a clangRewrite.a clangSema.a	\
            clangDriver.a clangAST.a clangParse.a clangLex.a		\