Merged in autoconf branch.  This provides configuration via the autoconf
system.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7014 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Makefile b/lib/Makefile
index 73caa73..8364f3c 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -1,6 +1,8 @@
 LEVEL = ..
 
-PARALLEL_DIRS = VMCore Analysis Transforms AsmParser Bytecode Support CodeGen Target CWriter Reoptimizer
+PARALLEL_DIRS = VMCore Analysis Transforms AsmParser Bytecode Support CodeGen Target CWriter
+
+OPTIONAL_DIRS = Reoptimizer
 
 include $(LEVEL)/Makefile.common