diff --git a/cfg/avr.cfg b/cfg/avr.cfg
index e5d803b87..d584a8b55 100644
--- a/cfg/avr.cfg
+++ b/cfg/avr.cfg
@@ -35,8 +35,22 @@
   <define name="M_PI_2" value="1.57079632679489661923"/>
   <define name="M_PI_4" value="0.78539816339744830962"/>
   <define name="M_1_PI" value="0.31830988618379067154"/>
-  <define name="M_2_PI" value="0.63661977236758134308 "/> 
+  <define name="M_2_PI" value="0.63661977236758134308 "/>
   <define name="M_2_SQRTPI" value="1.12837916709551257390"/>
   <define name="M_SQRT2" value="1.41421356237309504880"/>
   <define name="M_SQRT1_2" value="0.70710678118654752440"/>
+  <define name="NAN" value="__builtin_nan(\”\”)"/>
+  <define name="powf" value="pow"/>
+  <define name="roundf" value="round"/>
+  <define name="signbitf" value="signbit"/>
+  <define name="sinf" value="sin"/>
+  <define name="sinhf" value="sinh"/> 
+  <define name="sqrtf" value="sqrt"/>
+  <define name="squaref" value="square"/>
+  <define name="tanf" value="tan"/>
+  <define name="tanhf" value="tanh"/>
+  <define name="truncf" value="trunc"/>
+  <!-- The rest of the trigonometric functions are defined in std.cfg -->
+  <!-- setjmp.h --> 
+                      
 </def>