-XBT_PUBLIC xbt_matrix_t xbt_matrix_double_new_zeros(int lines, int rows);
-XBT_PUBLIC xbt_matrix_t xbt_matrix_double_new_id(int lines, int rows);
-XBT_PUBLIC xbt_matrix_t xbt_matrix_double_new_rand(int lines, int rows);
-XBT_PUBLIC xbt_matrix_t xbt_matrix_double_new_seq(int lines, int rows);
-XBT_PUBLIC xbt_matrix_t xbt_matrix_double_new_mult(xbt_matrix_t A,xbt_matrix_t B);
-XBT_PUBLIC void xbt_matrix_double_addmult(xbt_matrix_t A,xbt_matrix_t B,
+XBT_PUBLIC(xbt_matrix_t) xbt_matrix_double_new_zeros(int lines, int rows);
+XBT_PUBLIC(xbt_matrix_t) xbt_matrix_double_new_id(int lines, int rows);
+XBT_PUBLIC(xbt_matrix_t) xbt_matrix_double_new_rand(int lines, int rows);
+XBT_PUBLIC(xbt_matrix_t) xbt_matrix_double_new_seq(int lines, int rows);
+XBT_PUBLIC(xbt_matrix_t) xbt_matrix_double_new_mult(xbt_matrix_t A,xbt_matrix_t B);
+XBT_PUBLIC(void) xbt_matrix_double_addmult(xbt_matrix_t A,xbt_matrix_t B,