Makefile calls imake again but with ignored CC/LD.
Passing only if set rather than use defaults.
diff --git a/xmkmf.in b/xmkmf.in
index 5da01c0..426f9ee 100644
--- a/xmkmf.in
+++ b/xmkmf.in
@@ -54,11 +54,11 @@ case "$do_all" in
 yes)
     imake $imake_defines $args &&
     echo "make Makefiles" &&
-    make Makefiles &&
+    make ${CC:+CC="$CC"} ${LD:+LD="$LD"} Makefiles &&
     echo "make includes" &&
-    make includes &&
+    make ${CC:+CC="$CC"} ${LD:+LD="$LD"} includes &&
     echo "make depend" &&
-    make depend
+    make ${CC:+CC="$CC"} ${LD:+LD="$LD"} depend
     ;;
 *)
     imake $imake_defines $args