diff --git a/Makefile.config.in b/Makefile.config.in
index 4bf59635482..0ff3286b11f 100644
--- a/Makefile.config.in
+++ b/Makefile.config.in
@@ -150,11 +150,6 @@ ifndef LLVM_SRC_ROOT
 LLVM_SRC_ROOT := $(BUILD_SRC_ROOT)
 endif
 
-# Set SourceDir for backwards compatbility.
-ifndef SourceDir
-SourceDir=$(BUILD_SRC_DIR)
-endif
-
 # Handle configured libraries
 HAVE_BZIP2 := @HAVE_BZIP2@
 HAVE_ZLIB  := @HAVE_ZLIB@