+: argument order is deliberate, as the flag will start with - which set could
+: think is an option
+checkccflag='check=$1; flag=$2; callback=$3;
+echo " ";
+echo "Checking if your compiler accepts $flag" 2>&1;
+echo "int main(void) { return 0; }" > gcctest.c;
+if $cc -O2 $flag -o gcctest gcctest.c && ./gcctest; then
+ echo "Yes, it does." 2>&1;
+ case "$ccflags" in
+ *$check*)
+ echo "Leaving current flags $ccflags alone." 2>&1
+ ;;
+ *) dflt="$dflt $flag";
+ eval $callback
+ ;;
+ esac
+else
+ echo "Nope, it does not, but that is ok." 2>&1;
+fi
+'
+