diff --git a/src/frontend/error.c b/src/frontend/error.c
index b3b24f29c..906aad9e0 100644
--- a/src/frontend/error.c
+++ b/src/frontend/error.c
@@ -23,7 +23,7 @@ extern void shared_exit(int status);
 char ErrorMessage[1024];
 
 
-void
+ATTRIBUTE_NORETURN void
 controlled_exit(int status)
 {
 #ifdef HAS_WINGUI
diff --git a/src/frontend/inpcom.c b/src/frontend/inpcom.c
index d28cfffc0..e7a8465c2 100644
--- a/src/frontend/inpcom.c
+++ b/src/frontend/inpcom.c
@@ -3489,7 +3489,6 @@ get_param_name(char *line)
     if (!equal_ptr) {
         fprintf(stderr, "ERROR: could not find '=' on parameter line '%s'!\n", line);
         controlled_exit(EXIT_FAILURE);
-        return NULL;
     }
 
     equal_ptr = skip_back_ws_(equal_ptr, line);
@@ -3879,7 +3878,6 @@ inp_reorder_params_subckt(struct names *subckt_w_params, struct line *subckt_car
 
     /* the terminating `.ends' deck wasn't found */
     controlled_exit(EXIT_FAILURE);
-    return NULL;
 }
 
 
diff --git a/src/include/ngspice/ngspice.h b/src/include/ngspice/ngspice.h
index 3df2b6f64..e4f1b3167 100644
--- a/src/include/ngspice/ngspice.h
+++ b/src/include/ngspice/ngspice.h
@@ -213,6 +213,14 @@ extern double x_atanh(double);
 #define NAN (0.0/0.0)
 #endif
 
+#if defined(__GNUC__)
+#define ATTRIBUTE_NORETURN __attribute__ ((noreturn))
+#elif defined(_MSC_VER)
+#define ATTRIBUTE_NORETURN __declspec (noreturn)
+#else
+#define ATTRIBUTE_NORETURN
+#endif
+
 /* Fast random number generator */
 //#define FastRand
 #define WaGauss
@@ -308,11 +316,7 @@ extern void SetAnalyse(char *analyse, int percent);
 
 void soa_printf(CKTcircuit *ckt, GENinstance *instance, const char *fmt, ...);
 
-#ifdef __GNUC__
-extern void controlled_exit(int status) __attribute__ ((noreturn));
-#else
-extern void controlled_exit(int status);
-#endif
+ATTRIBUTE_NORETURN void controlled_exit(int status);
 
 
 /* macro to ignore unused variables and parameters */
diff --git a/src/main.c b/src/main.c
index bebfe10a5..dbaf372a9 100644
--- a/src/main.c
+++ b/src/main.c
@@ -154,7 +154,7 @@ struct variable *(*if_getparam)(CKTcircuit *ckt, char **name, char *param, int i
 
 /* static functions */
 int SIMinit(IFfrontEnd *frontEnd, IFsimulator **simulator);
-static void sp_shutdown(int exitval);
+static ATTRIBUTE_NORETURN void sp_shutdown(int exitval);
 static void app_rl_readlines(void);
 
 #if defined(HAVE_GNUREADLINE) || defined(HAVE_BSDEDITLINE)
@@ -520,7 +520,7 @@ SIMinit(IFfrontEnd *frontEnd, IFsimulator **simulator)
 
 /* -------------------------------------------------------------------------- */
 /* Shutdown gracefully. */
-static void
+static ATTRIBUTE_NORETURN void
 sp_shutdown(int exitval)
 {
     destroy_ivars();
@@ -1336,7 +1336,6 @@ main(int argc, char **argv)
         }
 
         sp_shutdown(EXIT_NORMAL);
-        return 0;
     }  /* ---  if (ft_batchmode) ---  */
 
 
diff --git a/src/spicelib/devices/cpl/cplload.c b/src/spicelib/devices/cpl/cplload.c
index 49601cb2d..952fa4fcf 100644
--- a/src/spicelib/devices/cpl/cplload.c
+++ b/src/spicelib/devices/cpl/cplload.c
@@ -786,7 +786,6 @@ errordetect:
    fprintf(stderr,	"your maximum time step	is too large for tau.\n");
    fprintf(stderr,	"decrease max time step	in .tran card and try again\n");
    controlled_exit(0);
-   return(0);
 }