diff --git a/src/tensormatrix_mpi.cpp b/src/tensormatrix_mpi.cpp
index 9ede677061269b81ccf4d2a5f5bf67faf83a9aaa..ef6a4c915626e11579737d1d69aa8299e5485cef 100644
--- a/src/tensormatrix_mpi.cpp
+++ b/src/tensormatrix_mpi.cpp
@@ -39,8 +39,8 @@ real	3m31,034s
 MPI_Datatype DT_PARAMETERS;
 MPI_Datatype DT_PARAMETERS_2;
 
-int nbforemen = NBFOREMEN;     /* Number of foremen to use with the hierarchical M/W */
-int maxresult = MAXRESULT;     /* Maximum results in the result queue, addslave version */
+unsigned int nbforemen = NBFOREMEN;     /* Number of foremen to use with the hierarchical M/W */
+unsigned int maxresult = MAXRESULT;     /* Maximum results in the result queue, addslave version */
 
 /*******************************************************************************
  *                               Main function                                 *
diff --git a/src/utils_parall.h b/src/utils_parall.h
index 2d5cd4b9fafa69c749613858aedbd3d7f4f90134..94f18ff793f21feb515045b0f0c7e17d9fd50ca1 100644
--- a/src/utils_parall.h
+++ b/src/utils_parall.h
@@ -55,7 +55,7 @@ gi::ex add_expressions( std::vector<std::string>, gi::lst );
 extern MPI_Datatype DT_PARAMETERS;
 extern MPI_Datatype DT_PARAMETERS_2;
 
-extern int nbforemen;     /* Number of foremen to use with the hierarchical M/W */
-extern int maxresult;     /* Maximum results in the result queue, addslave version */
+extern unsigned int nbforemen;     /* Number of foremen to use with the hierarchical M/W */
+extern unsigned int maxresult;     /* Maximum results in the result queue, addslave version */
 
 #endif // _UTILS_PARALL_H_