diff --git a/Makefile.config.in b/Makefile.config.in
index 84f3c1f9e56..8918e8339eb 100644
--- a/Makefile.config.in
+++ b/Makefile.config.in
@@ -48,6 +48,7 @@ MV      = mv
 INSTALL = @INSTALL@
 DOT     = @DOT@
 ETAGS   = @ETAGS@
+ETAGSFLAGS = @ETAGSFLAGS@
 
 # Determine the target for which LLVM should generate code.
 LLVMGCCARCH := @target@/3.4-llvm