Index: ../trunk-jpl/src/c/analyses/LsfReinitializationAnalysis.cpp
===================================================================
--- ../trunk-jpl/src/c/analyses/LsfReinitializationAnalysis.cpp	(revision 17335)
+++ ../trunk-jpl/src/c/analyses/LsfReinitializationAnalysis.cpp	(revision 17336)
@@ -370,7 +370,7 @@
 	/* insert signed_distance into vec_signed_dist, if computed distance is smaller */
 	for(i=0;i<numvertices;i++){
 		vec_signed_dist->GetValue(&lsf_old, element->vertices[i]->Sid());
-		if(isnan(lsf_old) || fabs(signed_dist[i])<fabs(lsf_old))
+		if(xIsNan<IssmDouble>(lsf_old) || fabs(signed_dist[i])<fabs(lsf_old))
 			vec_signed_dist->SetValue(element->vertices[i]->Sid(),signed_dist[i],INS_VAL);
 	}