diff --git a/eo/app/gpsymreg/fitness.h b/eo/app/gpsymreg/fitness.h
index eca800f0..35563599 100644
--- a/eo/app/gpsymreg/fitness.h
+++ b/eo/app/gpsymreg/fitness.h
@@ -202,14 +202,11 @@ class RegFitness: public eoEvalFunc< eoParseTree<FType, TreeNode> >
 					
 					fit += pow(target - output, 2);
 				}
-				// check if the fitness is valid
 				// some versions of gcc (e.g. 2.95.2 on solaris) don't have isinf(x) defined
-				#ifdef isinf
 				if (isinf(fit) == 0)
 					fitness[NORMAL] = fit;
 				else
 					fitness[NORMAL] = MAXFLOAT;	
-				#endif
 				
 				fitness[SMALLESTSIZE] =  _eo.size() / (1.0*parameter.MaxSize);
 				_eo.fitness(fitness);