debug: Print debug statements only from within host code

Author: giacomofiorin

src/colvarmodule.h

@@ -374,9 +374,13 @@ static inline real acos(real const &x)
   std::vector<colvarbias *> *biases_active();
 
   /// \brief Whether debug output should be enabled (compile-time option)
-  static inline bool debug()
+  static inline bool constexpr debug()
   {
+#if (defined(__HIP_DEVICE_COMPILE__)) || (defined(__CUDA_ARCH__))
+    return false;
+#else
     return COLVARS_DEBUG;
+#endif
   }
 
   /// How many objects (variables and biases) are configured yet?

src/colvars_system.h

@@ -154,7 +154,7 @@ inline COLVARS_HOST_DEVICE void cvm::system_boundary_conditions::set_boundaries(
     reciprocal_cell_z = v_xy / (v_xy * unit_cell_z);
   }
 
-  if (true) {
+  if (cvm::debug()) {
     cvm::log("periodic_x = " + cvm::to_str(periodic_x));
     cvm::log("periodic_y = " + cvm::to_str(periodic_y));
     cvm::log("periodic_z = " + cvm::to_str(periodic_z));