Patch taken from the Sage packaging system.

diff -Naur lcalc-1.23-vanilla/include/Ldirichlet_series.h lcalc-1.23-fixed-gcc.4.9/include/Ldirichlet_series.h
--- lcalc-1.23-vanilla/include/Ldirichlet_series.h	2012-08-08 23:21:55.000000000 +0200
+++ lcalc-1.23-fixed-gcc.4.9/include/Ldirichlet_series.h	2014-04-21 14:37:59.027464849 +0200
@@ -43,7 +43,7 @@
  //XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 template <class ttype>
 Complex L_function <ttype>::
-dirichlet_series(Complex s, long long N=-1)
+dirichlet_series(Complex s, long long N)
 {
     Complex z=0.;
     long long m,n;
diff -Naur lcalc-1.23-vanilla/include/L.h lcalc-1.23-fixed-gcc.4.9/include/L.h
--- lcalc-1.23-vanilla/include/L.h	2012-08-08 23:21:55.000000000 +0200
+++ lcalc-1.23-fixed-gcc.4.9/include/L.h	2014-04-21 14:32:04.003467348 +0200
@@ -491,7 +491,7 @@
 
     //#include "Ldirichlet_series.h" //for computing Dirichlet series
     Complex partial_dirichlet_series(Complex s, long long N1, long long N2);
-    Complex dirichlet_series(Complex s, long long N);
+    Complex dirichlet_series(Complex s, long long N=-1LL);
 
     //#include "Ltaylor_series.h" //for computing taylor series for Dirichlet series
     //void compute_taylor_series(int N, int K, Complex s_0, Complex *series);
