diff --git a/test_regress/Makefile_obj b/test_regress/Makefile_obj
index c6bdd069b..2281352f6 100644
--- a/test_regress/Makefile_obj
+++ b/test_regress/Makefile_obj
@@ -31,6 +31,7 @@ CPPFLAGS += -DVERILATOR=1
 # Needed by tracing routines
 CPPFLAGS += -DVL_DEBUG=1
 CPPFLAGS += -DVM_PREFIX=$(VM_PREFIX)
+CPPFLAGS += -DVM_PREFIX_INCLUDE="<$(VM_PREFIX).h>"
 CPPFLAGS += $(CPPFLAGS_DRIVER)
 CPPFLAGS += $(CPPFLAGS_DRIVER2)
 CPPFLAGS += $(CPPFLAGS_ADD)
diff --git a/test_regress/t/t_clk_2in.cpp b/test_regress/t/t_clk_2in.cpp
index c12350d60..74e946050 100644
--- a/test_regress/t/t_clk_2in.cpp
+++ b/test_regress/t/t_clk_2in.cpp
@@ -6,11 +6,7 @@
 // without warranty, 2010 by Wilson Snyder.
 
 #include <verilated.h>
-#ifdef T_CLK_2IN_VEC
-# include "Vt_clk_2in_vec.h"
-#else
-# include "Vt_clk_2in.h"
-#endif
+#include VM_PREFIX_INCLUDE
 
 unsigned int main_time = false;
 
diff --git a/test_regress/t/t_dist_whitespace.pl b/test_regress/t/t_dist_whitespace.pl
index 93c17dc3c..925b5a5d6 100755
--- a/test_regress/t/t_dist_whitespace.pl
+++ b/test_regress/t/t_dist_whitespace.pl
@@ -14,12 +14,19 @@ my $Debug;
 my %files = %{get_manifest_files($root)};
 
 foreach my $file (sort keys %files) {
-    my $contents = file_contents("$root/$file");
+    my $filename = "$root/$file";
+    my $contents = file_contents($filename);
     if ($file =~ /\.out$/) {
 	# Ignore golden files
     } elsif ($contents =~ /[\001\002\003\004\005\006]/) {
 	# Ignore binrary files
     } elsif ($contents =~ /[ \t]\n/) {
+	if ($ENV{HARNESS_UPDATE_GOLDEN}) {
+	    $contents =~ s/[ \t]+\n/\n/g;
+	    $warns{$file} = "Updated whitespace at $file";
+	    write_wholefile($filename, $contents);
+	    next;
+	}
         my @lines = split(/\n/, $contents);
         my $line_no = 0;
         foreach my $line (@lines) {
@@ -37,7 +44,13 @@ foreach my $file (sort keys %files) {
 
 if (keys %warns) {
     # First warning lists everything as that's shown in the driver summary
-    $Self->error("Files have whitespace errors: ",join(' ',sort keys %warns));
+    if ($ENV{HARNESS_UPDATE_GOLDEN}) {
+	$Self->error("Updated files with whitespace errors: ",join(' ',sort keys %warns));
+	$Self->error("To auto-fix: HARNESS_UPDATE_GOLDEN=1 {command} or --golden");
+    } else {
+	$Self->error("Files have whitespace errors: ",join(' ',sort keys %warns));
+	$Self->error("To auto-fix: HARNESS_UPDATE_GOLDEN=1 {command} or --golden");
+    }
     foreach my $file (sort keys %warns) {
 	$Self->error($warns{$file});
     }
diff --git a/test_regress/t/t_mem_multi_io2.cpp b/test_regress/t/t_mem_multi_io2.cpp
index f4fbfa4d6..b495e661f 100644
--- a/test_regress/t/t_mem_multi_io2.cpp
+++ b/test_regress/t/t_mem_multi_io2.cpp
@@ -3,13 +3,7 @@
 // This file ONLY is placed into the Public Domain, for any use,
 // without warranty, 2008 by Lane Brooks
 
-#if defined(T_MEM_MULTI_IO2_CC)
-# include "Vt_mem_multi_io2_cc.h"
-#elif defined(T_MEM_MULTI_IO2_SC)
-# include "Vt_mem_multi_io2_sc.h"
-#else
-# error "Unknown test"
-#endif
+#include VM_PREFIX_INCLUDE
 
 VM_PREFIX* tb = NULL;
 bool pass = true;
diff --git a/test_regress/t/t_mem_multi_io3.cpp b/test_regress/t/t_mem_multi_io3.cpp
index 8f001d86f..4df0e1970 100644
--- a/test_regress/t/t_mem_multi_io3.cpp
+++ b/test_regress/t/t_mem_multi_io3.cpp
@@ -3,13 +3,7 @@
 // This file ONLY is placed into the Public Domain, for any use,
 // without warranty.
 
-#if defined(T_MEM_MULTI_IO3_CC)
-# include "Vt_mem_multi_io3_cc.h"
-#elif defined(T_MEM_MULTI_IO3_SC)
-# include "Vt_mem_multi_io3_sc.h"
-#else
-# error "Unknown test"
-#endif
+#include VM_PREFIX_INCLUDE
 
 VM_PREFIX* tb = NULL;
 bool pass = true;
diff --git a/test_regress/t/t_trace_cat.cpp b/test_regress/t/t_trace_cat.cpp
index 326b3abcf..08786d9ea 100644
--- a/test_regress/t/t_trace_cat.cpp
+++ b/test_regress/t/t_trace_cat.cpp
@@ -8,15 +8,7 @@
 #include <verilated.h>
 #include <verilated_vcd_c.h>
 
-#if defined(T_TRACE_CAT)
-# include "Vt_trace_cat.h"
-#elif defined(T_TRACE_CAT_REOPEN)
-# include "Vt_trace_cat_reopen.h"
-#elif defined(T_TRACE_CAT_RENEW)
-# include "Vt_trace_cat_renew.h"
-#else
-# error "Unknown test"
-#endif
+#include VM_PREFIX_INCLUDE
 
 unsigned long long main_time = 0;
 double sc_time_stamp() {
diff --git a/test_regress/t/t_trace_timescale.cpp b/test_regress/t/t_trace_timescale.cpp
index 96632f559..7c9b86a5f 100644
--- a/test_regress/t/t_trace_timescale.cpp
+++ b/test_regress/t/t_trace_timescale.cpp
@@ -8,11 +8,7 @@
 #include <verilated.h>
 #include <verilated_vcd_c.h>
 
-#if defined(T_TRACE_TIMESCALE)
-# include "Vt_trace_timescale.h"
-#else
-# error "Unknown test"
-#endif
+#include VM_PREFIX_INCLUDE
 
 unsigned long long main_time = 0;
 double sc_time_stamp() {
diff --git a/test_regress/t/t_tri_gate.cpp b/test_regress/t/t_tri_gate.cpp
index 1960985f7..b90e6a4d0 100644
--- a/test_regress/t/t_tri_gate.cpp
+++ b/test_regress/t/t_tri_gate.cpp
@@ -3,23 +3,7 @@
 // This file ONLY is placed into the Public Domain, for any use,
 // without warranty, 2008 by Lane Brooks
 
-#ifdef T_COND
-# include "Vt_tri_gate_cond.h"
-#elif defined(T_BUFIF0)
-# include "Vt_tri_gate_bufif0.h"
-#elif defined(T_BUFIF1)
-# include "Vt_tri_gate_bufif1.h"
-#elif defined(T_NOTIF0)
-# include "Vt_tri_gate_notif0.h"
-#elif defined(T_NOTIF1)
-# include "Vt_tri_gate_notif1.h"
-#elif defined(T_PMOS)
-# include "Vt_tri_gate_pmos.h"
-#elif defined(T_NMOS)
-# include "Vt_tri_gate_nmos.h"
-#else
-# error "Unknown test"
-#endif
+#include VM_PREFIX_INCLUDE
 
 VM_PREFIX* tb = NULL;
 
diff --git a/test_regress/t/t_var_pinsizes.cpp b/test_regress/t/t_var_pinsizes.cpp
index 995e00840..fba136f42 100644
--- a/test_regress/t/t_var_pinsizes.cpp
+++ b/test_regress/t/t_var_pinsizes.cpp
@@ -1,26 +1,6 @@
 // -*- mode: C++; c-file-style: "cc-mode" -*-
 
-#ifdef T_VAR_PINS_CC
-# include "Vt_var_pins_cc.h"
-#elif defined(T_VAR_PINS_SC1)
-# include "Vt_var_pins_sc1.h"
-#elif defined(T_VAR_PINS_SC2)
-# include "Vt_var_pins_sc2.h"
-#elif defined(T_VAR_PINS_SC32)
-# include "Vt_var_pins_sc32.h"
-#elif defined(T_VAR_PINS_SC64)
-# include "Vt_var_pins_sc64.h"
-#elif defined(T_VAR_PINS_SCUI)
-# include "Vt_var_pins_scui.h"
-#elif defined(T_VAR_PINS_SC_UINT)
-# include "Vt_var_pins_sc_uint.h"
-#elif defined(T_VAR_PINS_SC_BIGUINT)
-# include "Vt_var_pins_sc_biguint.h"
-#elif defined(T_VAR_PINS_SC_UINT_BIGUINT)
-# include "Vt_var_pins_sc_uint_biguint.h"
-#else
-# error "Unknown test"
-#endif
+#include VM_PREFIX_INCLUDE
 
 VM_PREFIX* tb = NULL;
 
diff --git a/test_regress/t/t_include_all.pl b/test_regress/t/t_verilated_all.pl
similarity index 93%
rename from test_regress/t/t_include_all.pl
rename to test_regress/t/t_verilated_all.pl
index 03a364f51..5799c25a2 100755
--- a/test_regress/t/t_include_all.pl
+++ b/test_regress/t/t_verilated_all.pl
@@ -36,7 +36,7 @@ foreach my $dfile (glob("$Self->{obj_dir}/*.d")) {
 foreach my $file (sort keys %hit) {
     if (!$hit{$file}
         && $file !~ /_sc/) {
-        $Self->error("Include file not covered by t_include_all test: ",$file);
+        $Self->error("Include file not covered by t_verilated_all test: ",$file);
     }
 }
 
diff --git a/test_regress/t/t_include_all.v b/test_regress/t/t_verilated_all.v
similarity index 100%
rename from test_regress/t/t_include_all.v
rename to test_regress/t/t_verilated_all.v
diff --git a/test_regress/t/t_include_all_newest.pl b/test_regress/t/t_verilated_all_newest.pl
similarity index 95%
rename from test_regress/t/t_include_all_newest.pl
rename to test_regress/t/t_verilated_all_newest.pl
index dbe936ef9..183c15808 100755
--- a/test_regress/t/t_include_all_newest.pl
+++ b/test_regress/t/t_verilated_all_newest.pl
@@ -7,7 +7,7 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-top_filename("t/t_include_all.v");
+top_filename("t/t_verilated_all.v");
 
 my $root = "..";
 
diff --git a/test_regress/t/t_include_all_oldest.pl b/test_regress/t/t_verilated_all_oldest.pl
similarity index 95%
rename from test_regress/t/t_include_all_oldest.pl
rename to test_regress/t/t_verilated_all_oldest.pl
index a0077af6f..5e781bc0d 100755
--- a/test_regress/t/t_include_all_oldest.pl
+++ b/test_regress/t/t_verilated_all_oldest.pl
@@ -7,7 +7,7 @@ if (!$::Driver) { use FindBin; exec("$FindBin::Bin/bootstrap.pl", @ARGV, $0); di
 # Lesser General Public License Version 3 or the Perl Artistic License
 # Version 2.0.
 
-top_filename("t/t_include_all.v");
+top_filename("t/t_verilated_all.v");
 
 my $root = "..";