ChibiOS 2.6.8, until I can figure out where to get it from git.

firmware/chibios/testhal/STM32F4xx/IRQ_STORM_FPU/extfunc.c

@@ -0,0 +1,23 @@
+/*
+    ChibiOS/RT - Copyright (C) 2006-2013 Giovanni Di Sirio
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+*/
+
+float ff1(float par) {
+  return par;
+}
+
+float ff2(float par1, float par2, float par3, float par4) {
+  return (par1 + par2) * (par3 + par4);
+}