--- a/source/diag.c
+++ b/source/diag.c
@@ -958,7 +958,7 @@
  * The pointer returned (and the ones included in the struct)  
  * has to be deallocted explicitely from memory. 
  */ 
-inline struct simple_diag_col* find_diags_dialign(struct scr_matrix *smatrix,  
+static inline struct simple_diag_col* find_diags_dialign(struct scr_matrix *smatrix,  
 				struct prob_dist *pdist, struct seq* seq1,  
 				struct seq* seq2, struct alignment *algn, 
 				 long double **tmp_dist, int round) {