use the compiler passed in $CC
--- iproute2-2.6.29-1.orig/configure	2009-03-24 23:40:54.000000000 +0100
+++ iproute2-2.6.29-1/configure	2009-08-22 02:23:52.642364236 +0200
@@ -16,7 +16,7 @@ int main(int argc, char **argv) {
 	return 0;
 }
 EOF
-gcc -I$INCLUDE -o /tmp/atmtest /tmp/atmtest.c -latm >/dev/null 2>&1 
+$CC -I$INCLUDE -o /tmp/atmtest /tmp/atmtest.c -latm >/dev/null 2>&1 
 if [ $? -eq 0 ]
 then
     echo "TC_CONFIG_ATM:=y" >>Config
@@ -49,7 +49,7 @@ int main(int argc, char **argv) {
 }
 
 EOF
-gcc -I$INCLUDE $IPTC -o /tmp/ipttest /tmp/ipttest.c $IPTL -ldl >/dev/null 2>&1
+$CC -I$INCLUDE $IPTC -o /tmp/ipttest /tmp/ipttest.c $IPTL -ldl >/dev/null 2>&1
 
 if [ $? -eq 0 ]
 then
@@ -81,7 +81,7 @@ int main(int argc, char **argv) {
 }
 
 EOF
-gcc -I$INCLUDE $IPTC -o /tmp/ipttest /tmp/ipttest.c $IPTL -ldl >/dev/null 2>&1
+$CC -I$INCLUDE $IPTC -o /tmp/ipttest /tmp/ipttest.c $IPTL -ldl >/dev/null 2>&1
 
 if [ $? -eq 0 ]
 then