don't pass -Wl,-exported_symbol -Wl,_main to the linker when building on

Tiger.  PR3743


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66550 91177308-0d34-0410-b5e6-96231b3b80d8

Makefile.rules

@@ -469,6 +469,8 @@ ifeq ($(OS),Darwin)
   DARWIN_VERSION := `sw_vers -productVersion`
   # Strip a number like 10.4.7 to 10.4
   DARWIN_VERSION := $(shell echo $(DARWIN_VERSION)| sed -E 's/(10.[0-9]).*/\1/')
+  # Get "4" out of 10.4 for later pieces in the makefile.
+  DARWIN_MAJVERS := $(shell echo $(DARWIN_VERSION)| sed -E 's/10.([0-9]).*/\1/')
      
   SharedLinkOptions=-Wl,-flat_namespace -Wl,-undefined -Wl,suppress -bundle \
                     -mmacosx-version-min=$(DARWIN_VERSION)
@@ -1116,8 +1118,12 @@ endif
 # startup time by 4x on darwin in some cases.
 ifdef TOOL_NO_EXPORTS
 ifeq ($(OS),Darwin)
+
+# Tiger tools don't support this.
+ifneq ($(DARWIN_MAJVERS),4)
 LD.Flags += -Wl,-exported_symbol -Wl,_main
 endif
+endif
 
 ifeq ($(OS), $(filter $(OS), Linux NetBSD FreeBSD))
 LD.Flags += -Wl,--version-script=$(LLVM_SRC_ROOT)/autoconf/ExportMap.map