Consistently use ycur for user RHS routines

src/arkode/arkode_erkstep.c

@@ -781,7 +781,7 @@ int erkStep_TakeStep(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   SUNLogExtraDebugVec(ARK_LOGGER, "stage", ark_mem->yn, "z_0(:) =");
 
   /* Call the full RHS if needed. If this is the first step then we may need to
-     evaluate or copy the RHS values from an  earlier evaluation (e.g., to
+     evaluate or copy the RHS values from an earlier evaluation (e.g., to
      compute h0). For subsequent steps treat this RHS evaluation as an
      evaluation at the end of the just completed step to potentially reuse
      (FSAL methods) RHS evaluations from the end of the last step. */

src/arkode/arkode_mristep.c

@@ -1324,14 +1324,14 @@ int mriStep_Init(ARKodeMem ark_mem, sunrealtype tout, int init_type)
     if (ark_mem->hin == ZERO)
     {
       /*   tempv1 = fslow(t0, y0) */
-      if (mriStep_SlowRHS(ark_mem, ark_mem->tcur, ark_mem->yn, ark_mem->tempv1,
+      if (mriStep_SlowRHS(ark_mem, ark_mem->tn, ark_mem->yn, ark_mem->tempv1,
                           ARK_FULLRHS_START) != ARK_SUCCESS)
       {
         arkProcessError(ark_mem, ARK_RHSFUNC_FAIL, __LINE__, __func__, __FILE__,
                         "error calling slow RHS function(s)");
         return (ARK_RHSFUNC_FAIL);
       }
-      retval = mriStep_Hin(ark_mem, ark_mem->tcur, tout, ark_mem->tempv1,
+      retval = mriStep_Hin(ark_mem, ark_mem->tn, tout, ark_mem->tempv1,
                            &(ark_mem->hin));
       if (retval != ARK_SUCCESS)
       {
@@ -1870,7 +1870,7 @@ int mriStep_TakeStepMRIGARK(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPt
   SUNLogInfo(ARK_LOGGER, "begin-stages-list",
              "stage = 0, stage type = %d, tcur = " SUN_FORMAT_G, MRISTAGE_FIRST,
              ark_mem->tcur);
-  SUNLogExtraDebugVec(ARK_LOGGER, "slow stage", ark_mem->ycur, "z_0(:) =");
+  SUNLogExtraDebugVec(ARK_LOGGER, "slow stage", ark_mem->yn, "z_0(:) =");
 
   /* Evaluate the slow RHS functions if needed. NOTE: we decide between calling the
      full RHS function (if ark_mem->fn is non-NULL and MRIStep is not an inner
@@ -2917,7 +2917,8 @@ int mriStep_TakeStepMERK(ARKodeMem ark_mem, sunrealtype* dsmPtr, int* nflagPtr)
   /* for adaptive computations, reset the inner integrator to the beginning of this step */
   if (!ark_mem->fixedstep)
   {
-    retval = mriStepInnerStepper_Reset(step_mem->stepper, t0, ark_mem->ycur);
+    retval = mriStepInnerStepper_Reset(step_mem->stepper, ark_mem->tn,
+                                       ark_mem->ycur);
     if (retval != ARK_SUCCESS)
     {
       arkProcessError(ark_mem, ARK_INNERSTEP_FAIL, __LINE__, __func__, __FILE__,