diff --git a/src/frontend/inp.c b/src/frontend/inp.c
index b164bc1fe..aba8450d1 100644
--- a/src/frontend/inp.c
+++ b/src/frontend/inp.c
@@ -960,8 +960,8 @@ inp_spsource(FILE *fp, bool comfile, char *filename, bool intfile)
                So again try to remove unused MOS models.
                All binning models are still here when w or l have been
                determined by an expression. */
-           if (newcompat.hs || newcompat.spe)
-              rem_unused_mos_models(deck->nextcard);
+//           if (newcompat.hs || newcompat.spe)
+//              rem_unused_mos_models(deck->nextcard);
 
             /* now load deck into ft_curckt -- the current circuit. */
             if(inp_dodeck(deck, tt, wl_first, FALSE, options, filename) != 0)
diff --git a/src/frontend/runcoms.c b/src/frontend/runcoms.c
index 9d52e192e..613be5d9e 100644
--- a/src/frontend/runcoms.c
+++ b/src/frontend/runcoms.c
@@ -14,6 +14,7 @@ Modified: 2000 AlansFixes
 #include "ngspice/ftedev.h"
 #include "ngspice/ftedebug.h"
 #include "ngspice/dvec.h"
+#include "ngspice/hash.h"
 
 #include "numparam/numpaif.h"
 
@@ -33,6 +34,7 @@ Modified: 2000 AlansFixes
 
 static int dosim(char *what, wordlist *wl);
 extern struct INPmodel *modtab;
+extern NGHASHPTR modtabhash;
 extern struct dbcomm *dbs;
 extern void NIresetwarnmsg(void);
 
@@ -107,6 +109,7 @@ com_scirc(wordlist *wl)
     ft_curckt = p;
     /* get the model table for the current circuit, store it in the global variable modtab */
     modtab = ft_curckt->ci_modtab;
+    modtabhash = ft_curckt->ci_modtabhash;
     /* get the database for save, iplot, stop */
     dbs = ft_curckt->ci_dbs;
     /* set the numparam dicos structure for use with measure */
diff --git a/src/frontend/runcoms2.c b/src/frontend/runcoms2.c
index ac6c9dead..baf43ee79 100644
--- a/src/frontend/runcoms2.c
+++ b/src/frontend/runcoms2.c
@@ -14,6 +14,7 @@ Author: 1985 Wayne A. Christopher, U. C. Berkeley CAD Group
 #include "ngspice/ftedebug.h"
 #include "ngspice/dvec.h"
 #include "ngspice/trandefs.h"
+#include "ngspice/hash.h"
 
 #include "circuits.h"
 #include "runcoms2.h"
@@ -33,6 +34,7 @@ Author: 1985 Wayne A. Christopher, U. C. Berkeley CAD Group
 
 extern void line_free_x(struct card *deck, bool recurse);
 extern INPmodel *modtab;
+extern NGHASHPTR modtabhash;
 
 #ifdef SHARED_MODULE
 extern void exec_controls(wordlist *newcontrols);
@@ -273,10 +275,11 @@ com_remcirc(wordlist *wl)
         prev = p;
     }
 
-    /* make first entry in ft_circuits the actual circuit (or NULL) */
+    /* make first entry in ft_circuits the current circuit (or NULL) */
     ft_curckt = ft_circuits;
     if (ft_curckt) {
         modtab = ft_curckt->ci_modtab;
+        modtabhash = ft_curckt->ci_modtabhash;
         dbs = ft_curckt->ci_dbs;
         nupa_set_dicoslist(ft_curckt->ci_dicos);
     }
diff --git a/src/frontend/spiceif.c b/src/frontend/spiceif.c
index 724e4f879..c135b37db 100644
--- a/src/frontend/spiceif.c
+++ b/src/frontend/spiceif.c
@@ -54,6 +54,7 @@ CDHW*/
 #include "ngspice/inpdefs.h"
 #include "ngspice/iferrmsg.h"
 #include "ngspice/ifsim.h"
+#include "ngspice/hash.h"
 
 #include "circuits.h"
 #include "spiceif.h"
@@ -75,6 +76,7 @@ CDHW*/
 #endif
 
 extern INPmodel *modtab;
+extern NGHASHPTR modtabhash;
 extern bool ft_batchmode;
 
 static struct variable *parmtovar(IFvalue *pv, IFparm *opt);
@@ -160,9 +162,11 @@ if_inpdeck(struct card *deck, INPtables **tab)
 
     /* Parse the .model lines. Enter the model into the global model table modtab. */
     modtab = NULL;
+    modtabhash = NULL;
     INPpas1(ckt, deck->nextcard, *tab);
     /* store the new model table in the current circuit */
     ft_curckt->ci_modtab = modtab;
+    ft_curckt->ci_modtabhash = modtabhash;
 
     /* Scan through the instance lines and parse the circuit. */
     INPpas2(ckt, deck->nextcard, *tab, ft_curckt->ci_defTask);
diff --git a/src/include/ngspice/cmproto.h b/src/include/ngspice/cmproto.h
index 129fbc23a..7ab6ffbd5 100644
--- a/src/include/ngspice/cmproto.h
+++ b/src/include/ngspice/cmproto.h
@@ -126,4 +126,6 @@ FILE *fopen_with_path(const char *path, const char *mode);
 
 #define CM_IGNORE(x) (void) (x)
 
+void cm_cexit(const int);
+
 #endif /* include guard */
diff --git a/src/include/ngspice/dllitf.h b/src/include/ngspice/dllitf.h
index b3a68c65d..1d9295d81 100644
--- a/src/include/ngspice/dllitf.h
+++ b/src/include/ngspice/dllitf.h
@@ -83,6 +83,7 @@ struct coreInfo_t {
 	void *    ((*dllitf_tmalloc)(size_t));
 	void *    ((*dllitf_trealloc)(const void *, size_t));
 	void      ((*dllitf_txfree)(const void *));
+	void      ((*dllitf_cexit)(const int));
 
 #ifdef KLU
         int ((*dllitf_MIFbindCSC) (GENmodel *, CKTcircuit *)) ;
diff --git a/src/include/ngspice/ftedefs.h b/src/include/ngspice/ftedefs.h
index 471f1c9b2..639707250 100644
--- a/src/include/ngspice/ftedefs.h
+++ b/src/include/ngspice/ftedefs.h
@@ -17,6 +17,7 @@ Author: 1985 Wayne A. Christopher, U. C. Berkeley CAD Group
 #include "ngspice/fteparse.h"
 #include "ngspice/fteinp.h"
 #include "ngspice/fteoptdefs.h"
+#include "ngspice/hash.h"
 
 struct ccom;
 
@@ -34,6 +35,7 @@ struct circ {
     CKTcircuit *ci_ckt;       /* The CKTcircuit structure. */
     INPtables  *ci_symtab;    /* The INP symbol table. */
     INPmodel   *ci_modtab;    /* The INP model table. */
+    NGHASHPTR  ci_modtabhash; /* The INP model hash table. */
     struct dbcomm *ci_dbs;    /* The database storing save, iplot, stop data */
     struct card *ci_deck;     /* The input deck. */
     struct card *ci_origdeck; /* The input deck, before subckt expansion. */
diff --git a/src/spicelib/parser/inpgmod.c b/src/spicelib/parser/inpgmod.c
index 6450abf6d..44dc93989 100644
--- a/src/spicelib/parser/inpgmod.c
+++ b/src/spicelib/parser/inpgmod.c
@@ -39,6 +39,7 @@ static int INPfindParm(char *name, IFparm *table, int numParms);
 #endif
 
 extern INPmodel *modtab;
+extern NGHASHPTR modtabhash;
 
 
 static IFparm *
@@ -342,6 +343,33 @@ INPgetMod(CKTcircuit *ckt, char *name, INPmodel **model, INPtables *tab)
     printf("In INPgetMod, examining model %s ...\n", name);
 #endif
 
+    modtmp = nghash_find(modtabhash, name);
+    if (modtmp) {
+        /* found the model in question - now instantiate if necessary */
+        /* and return an appropriate pointer to it */
+
+/* if illegal device type */
+        if (modtmp->INPmodType < 0) {
+#ifdef TRACE
+            printf("In INPgetMod, illegal device type for model %s ...\n", name);
+#endif
+            * model = NULL;
+            return tprintf("Unknown device type for model %s\n", name);
+        }
+
+        /* create unless model is already defined */
+        if (!modtmp->INPmodfast) {
+            int error = create_model(ckt, modtmp, tab);
+            if (error) {
+                *model = NULL;
+                return INPerror(error);
+            }
+        }
+
+        *model = modtmp;
+        return NULL;
+    }
+#if (0)
     for (modtmp = modtab; modtmp; modtmp = modtmp->INPnextModel) {
 
 #ifdef TRACE
@@ -374,7 +402,7 @@ INPgetMod(CKTcircuit *ckt, char *name, INPmodel **model, INPtables *tab)
             return NULL;
         }
     }
-
+#endif
 #ifdef TRACE
     printf("In INPgetMod, didn't find model for %s, using default ...\n", name);
 #endif
diff --git a/src/spicelib/parser/inpkmods.c b/src/spicelib/parser/inpkmods.c
index 8e356a840..1c0f75be3 100644
--- a/src/spicelib/parser/inpkmods.c
+++ b/src/spicelib/parser/inpkmods.c
@@ -1,8 +1,8 @@
 /**********
 Copyright 1990 Regents of the University of California.  All rights reserved.
-Author: 1985 Thomas L. Quarles
+Author: 1985 Thomas L. Quarles, 2023 Holger Vogt
 **********/
-/*
+/* Deletes the model table modtab and the hash table modtabhash.
  */
 
 #include "ngspice/ngspice.h"
@@ -11,21 +11,27 @@ Author: 1985 Thomas L. Quarles
 #include "ngspice/ftedefs.h"
 #include "inpxx.h"
 
-
-extern INPmodel *modtab;
+extern INPmodel* modtab;
+extern NGHASHPTR modtabhash;
 
 void INPkillMods(void)
 {
-    INPmodel *modtmp;
-    INPmodel *prev = NULL;
+    INPmodel* modtmp;
+    INPmodel* prev = NULL;
 
     for (modtmp = modtab; modtmp != NULL; modtmp = modtmp->INPnextModel) {
-	if (prev)
-	    FREE(prev);
-	prev = modtmp;
+        if (prev)
+            FREE(prev);
+        prev = modtmp;
     }
     if (prev)
-	FREE(prev);
+        FREE(prev);
     modtab = NULL;
     ft_curckt->ci_modtab = NULL;
+    /* free the hash table */
+    if (modtabhash) {
+        nghash_free(modtabhash, NULL, NULL);
+        modtabhash = NULL;
+    }
+    ft_curckt->ci_modtabhash = NULL;
 }
diff --git a/src/spicelib/parser/inpmkmod.c b/src/spicelib/parser/inpmkmod.c
index 456c4f5e4..055d7a66b 100644
--- a/src/spicelib/parser/inpmkmod.c
+++ b/src/spicelib/parser/inpmkmod.c
@@ -7,10 +7,14 @@ Author: 1985 Thomas L. Quarles
 #include <stdio.h>
 #include "ngspice/inpdefs.h"
 #include "ngspice/iferrmsg.h"
+#include "ngspice/hash.h"
 #include "inpxx.h"
 
 /*  global input model table.  */
 INPmodel *modtab = NULL;
+/* Global input model hash table.
+   The modelname is the key, the return value is the pointer to the model. */
+NGHASHPTR modtabhash = NULL;
 
 /*--------------------------------------------------------------
  * This fcn takes the model name and looks to see if it is already
@@ -21,33 +25,40 @@ INPmodel *modtab = NULL;
 
 int INPmakeMod(char *token, int type, struct card *line)
 {
-   register INPmodel **i;
-
-   /* First cycle through model table and see if model name
-      already exists in there.  If it does, just return. */
-   for (i = &modtab; *i != NULL; i = &((*i)->INPnextModel)) {
-      if (strcmp((*i)->INPmodName, token) == 0) {
-         return (OK);
-      }
+   register INPmodel *newm;
+   /* Initialze the hash table. The default key type is string.
+      The default comparison function is strcmp.*/
+   if (!modtabhash) {
+       modtabhash = nghash_init(NGHASH_MIN_SIZE);
+       nghash_unique(modtabhash, TRUE);
    }
+   /* If the model is already there, just return. */
+   else if (nghash_find(modtabhash, token))
+       return (OK);
 
-   /* Model name was not already in model table.  Therefore stick
-      it in the model table. Then return.  */
+   /* Model name was not already in model table. Therefore stick
+      it in the front of the model table, also into the model hash table.
+      Then return.  */
 
 #ifdef TRACE
    /* debug statement */
    printf("In INPmakeMod, about to insert new model name = %s . . .\n", token);
 #endif
 
-   *i = TMALLOC(INPmodel, 1);
-   if (*i == NULL)
+   newm = TMALLOC(INPmodel, 1);
+   if (newm == NULL)
       return (E_NOMEM);
 
-   (*i)->INPmodName = token;                 /* model name */
-   (*i)->INPmodType = type;                  /* model type */
-   (*i)->INPnextModel = NULL;   /* pointer to next model (end of list) */
-   (*i)->INPmodLine = line;                  /* model line */
-   (*i)->INPmodfast = NULL;
+   newm->INPmodName = token;                 /* model name */
+   newm->INPmodType = type;                  /* model type */
+   newm->INPnextModel = modtab;              /* pointer to second model */
+   newm->INPmodLine = line;                  /* model line */
+   newm->INPmodfast = NULL;
+
+   nghash_insert(modtabhash, token, newm);
+
+   modtab = newm;
+
    return (OK);
 }
 
diff --git a/src/spicelib/parser/inpptree.c b/src/spicelib/parser/inpptree.c
index 063bbd5f9..22d298489 100644
--- a/src/spicelib/parser/inpptree.c
+++ b/src/spicelib/parser/inpptree.c
@@ -12,6 +12,7 @@ Author: 1987 Wayne A. Christopher, U. C. Berkeley CAD Group
 #include "ngspice/iferrmsg.h"
 #include "ngspice/inpdefs.h"
 #include "ngspice/inpptree.h"
+#include "ngspice/randnumb.h"
 #include "inpxx.h"
 
 #include "inpptree-parser.h"
@@ -36,6 +37,8 @@ static INPparseNode *PTdifferentiate(INPparseNode * p, int varnum);
 static void free_tree(INPparseNode *);
 static void printTree(INPparseNode *);
 
+static double gauss(double nominal_val, double rel_variation, double sigma);
+
 
 /*
  * LAW for INPparseNode* generator and consumer functions:
@@ -1145,6 +1148,30 @@ INPparseNode *PT_mkfnode(const char *fname, INPparseNode * arg)
         return mkfirst(NULL, arg);
     }
 
+    /* This is used only to evaluate fcn gauss(a1, a2, a3) in .model files, where 
+       temper is used also. a1, a2, and a3 have to be constant double values. */
+    if (!strcmp("gauss", buf)) {
+        if (arg->type == PT_COMMA && arg->left->type == PT_COMMA) {
+
+            INPparseNode* arg1 = arg->left->left;
+            INPparseNode* arg2 = arg->left->right;
+            INPparseNode* arg3 = arg->right;
+            double a1 = arg1->constant;
+            double a2 = arg2->constant;
+            double a3 = arg3->constant;
+
+            if (a2 == 0.0 || a3 == 0.0) {
+                fprintf(stderr, "Error: bogus gauss form\n");
+                return mkfirst(NULL, arg); //return mkcon(a1);
+            }
+
+            return mkcon(gauss(a1, a2, a3));
+        }
+
+        fprintf(stderr, "Error: bogus gauss form\n");
+        return mkfirst(NULL, arg);
+    }
+
     for (i = 0; i < NUM_FUNCS; i++)
         if (!strcmp(funcs[i].name, buf))
             break;
@@ -1626,6 +1653,16 @@ void free_tree(INPparseNode *pt)
     txfree(pt);
 }
 
+static double
+gauss(double nominal_val, double rel_variation, double sigma)
+{
+    double stdvar;
+    if (rel_variation <= 0 || sigma <= 0)
+        return nominal_val;
+    stdvar = nominal_val * rel_variation / sigma;
+    return (nominal_val + stdvar * gauss1());
+}
+
 
 /* Debugging stuff. */
 
diff --git a/src/xspice/cm/cmexport.c b/src/xspice/cm/cmexport.c
index 2240eaf01..0e65a1f75 100644
--- a/src/xspice/cm/cmexport.c
+++ b/src/xspice/cm/cmexport.c
@@ -81,7 +81,8 @@ struct coreInfo_t  coreInfo =
   txfree,
   tmalloc,
   trealloc,
-  txfree
+  txfree,
+  cm_cexit
 #else
   GC_malloc,
   tcalloc,
diff --git a/src/xspice/cm/cmutil.c b/src/xspice/cm/cmutil.c
index c1953192c..ee69a0f99 100644
--- a/src/xspice/cm/cmutil.c
+++ b/src/xspice/cm/cmutil.c
@@ -36,7 +36,7 @@ INTERFACES
     cm_complex_subtract()
     cm_complex_multiply()
     cm_complex_divide()
-    
+    cm_cexit()
 
 REFERENCED FILES
 
@@ -51,6 +51,8 @@ NON-STANDARD FEATURES
 #include <stdio.h>
 #include <math.h>
 #include "ngspice/cm.h"
+
+extern void controlled_exit(const int);
  
 /* Corner Smoothing Function ************************************
 *                                                               *
@@ -525,4 +527,7 @@ Complex_t cm_complex_divide(Complex_t x, Complex_t y)
     return(c);
 }
 
-
+void cm_cexit(const int exitcode)
+{
+    controlled_exit(exitcode);
+}
diff --git a/src/xspice/icm/dlmain.c b/src/xspice/icm/dlmain.c
index c64668991..87f6050f9 100644
--- a/src/xspice/icm/dlmain.c
+++ b/src/xspice/icm/dlmain.c
@@ -430,6 +430,10 @@ void txfree(const void *ptr) {
 	(coreitf->dllitf_txfree)(ptr);
 }
 
+void cm_cexit(const int exitcode) {
+	(coreitf->dllitf_cexit)(exitcode);
+}
+
 #ifdef KLU
 int MIFbindCSC (GENmodel *inModel, CKTcircuit *ckt) {
     return (coreitf->dllitf_MIFbindCSC) (inModel, ckt) ;