diff --git a/lib/libm/common_source/pow.c b/lib/libm/common_source/pow.c
index 5121f304642..cb4fc5029f4 100644
--- a/lib/libm/common_source/pow.c
+++ b/lib/libm/common_source/pow.c
@@ -174,7 +174,8 @@ pow_P(x, y) double x, y;
 #endif
 {
 	struct Double s, t, __log__D();
-	double  __exp__D(), huge = 1e300, tiny = 1e-300;
+	double  __exp__D();
+	volatile double huge = 1e300, tiny = 1e-300;
 
 	if (x == zero)
 		if (y > zero)