diff --git a/tgt-vvp/eval_expr.c b/tgt-vvp/eval_expr.c
index 3dd12947f..eae28e858 100644
--- a/tgt-vvp/eval_expr.c
+++ b/tgt-vvp/eval_expr.c
@@ -731,8 +731,8 @@ static struct vector_info draw_binary_expr_le(ivl_expr_t exp,
       assert(ivl_expr_value(re) == IVL_VT_LOGIC
 	     || ivl_expr_value(re) == IVL_VT_BOOL);
 
-      lv.wid = 0;
-      rv.wid = 0;
+      lv.wid = 0;  lv.base=0;
+      rv.wid = 0;  rv.base=0;
 
       switch (ivl_expr_opcode(exp)) {
 	  case 'G':
diff --git a/vpi/sys_display.c b/vpi/sys_display.c
index 647612486..cc7caa172 100644
--- a/vpi/sys_display.c
+++ b/vpi/sys_display.c
@@ -1590,6 +1590,7 @@ static unsigned int get_format_char(char **rtn, int ljust, int plus,
     case 'u':
     case 'U':
       *idx += 1;
+      size = 0;  /* fallback value if errors */
       if (ljust != 0  || plus != 0 || ld_zero != 0 || width != -1 ||
           prec != -1) {
         vpi_printf("WARNING: invalid format %s%s.\n", info->name, fmtb);
@@ -1661,6 +1662,7 @@ static unsigned int get_format_char(char **rtn, int ljust, int plus,
     case 'z':
     case 'Z':
       *idx += 1;
+      size = 0;  /* fallback value if errors */
       if (ljust != 0  || plus != 0 || ld_zero != 0 || width != -1 ||
           prec != -1) {
         vpi_printf("WARNING: invalid format %s%s.\n", info->name, fmtb);
@@ -2161,6 +2163,7 @@ static PLI_INT32 sys_printtimescale_calltf(PLI_BYTE8*xx)
       vpiHandle scope;
       if (!argv) {
             vpiHandle parent = vpi_handle(vpiScope, sys);
+            scope = NULL;  /* fallback value if parent is NULL */
             while (parent) {
                    scope = parent;
                    parent = vpi_handle(vpiScope, scope);
@@ -2169,7 +2172,7 @@ static PLI_INT32 sys_printtimescale_calltf(PLI_BYTE8*xx)
             scope = vpi_scan(argv);
             vpi_free_object(argv);
       }
-      
+
       vpi_printf("Time scale of (%s) is ", vpi_get_str(vpiFullName, scope));
       vpi_printf("%s / ", pts_convert(vpi_get(vpiTimeUnit, scope)));
       vpi_printf("%s\n", pts_convert(vpi_get(vpiTimePrecision, scope)));
diff --git a/vvp/vpi_priv.cc b/vvp/vpi_priv.cc
index a7494cdcf..966567f2f 100644
--- a/vvp/vpi_priv.cc
+++ b/vvp/vpi_priv.cc
@@ -399,8 +399,10 @@ PLI_INT32 vpi_get_vlog_info(p_vpi_vlog_info vlog_info_p)
 
 void vpi_set_vlog_info(int argc, char** argv)
 {
-    vpi_vlog_info.product = "Icarus Verilog";
-    vpi_vlog_info.version = "$Name:  $";
+    static char icarus_product[] = "Icarus Verilog";
+    static char icarus_version[] = "$Name:  $";
+    vpi_vlog_info.product = icarus_product;
+    vpi_vlog_info.version = icarus_version;
     vpi_vlog_info.argc    = argc;
     vpi_vlog_info.argv    = argv;
 
diff --git a/vvp/vpi_vthr_vector.cc b/vvp/vpi_vthr_vector.cc
index e8af1d9a2..cc5b87e5a 100644
--- a/vvp/vpi_vthr_vector.cc
+++ b/vvp/vpi_vthr_vector.cc
@@ -40,7 +40,7 @@ struct __vpiVThrVec {
       unsigned bas;
       unsigned wid;
       unsigned signed_flag : 1;
-      char *name;
+      const char *name;
 };
 
 inline static
@@ -427,14 +427,14 @@ vpiHandle vpip_make_vthr_vector(unsigned base, unsigned wid, bool signed_flag)
       assert(wid < 65536);
       obj->wid = wid;
       obj->signed_flag = signed_flag? 1 : 0;
-      obj->name = "T<>";
+      obj->name = vpip_name_string("T<>");
 
       return &obj->base;
 }
 
 struct __vpiVThrWord {
       struct __vpiHandle base;
-      char* name;
+      const char* name;
       int subtype;
       unsigned index;
 };
@@ -545,7 +545,7 @@ vpiHandle vpip_make_vthr_word(unsigned base, const char*type)
       assert(type[0] == 'r');
 
       obj->base.vpi_type = &vpip_vthr_const_real_rt;
-      obj->name = "W<>";
+      obj->name = vpip_name_string("W<>");
       obj->subtype = vpiRealConst;
       assert(base < 65536);
       obj->index = base;