--- a/configure
+++ b/configure
@@ -1662,7 +1662,7 @@ INSTALL_STRIP_PROGRAM="\${SHELL} \$(inst
 
 
 
-CFLAGS="-g -Wall"
+CFLAGS="${CFLAGS} -g -Wall"
 
 ac_ext=c
 ac_cpp='$CPP $CPPFLAGS'