diff --git a/test_regress/driver.pl b/test_regress/driver.pl
index 846e74930..cb68f1885 100755
--- a/test_regress/driver.pl
+++ b/test_regress/driver.pl
@@ -969,9 +969,9 @@ sub compile {
 
     compile_vlt_cmd(%param);
 
-    if (!$self->{make_top_shell}) {
+    if (!$param{make_top_shell}) {
         $param{top_shell_filename}
-        = $self->{top_shell_filename} = $self->{top_filename};
+        = $self->{top_shell_filename} = "";
     } else {
         $param{top_shell_filename}
         = $self->{top_shell_filename} = "$self->{obj_dir}/$self->{VM_PREFIX}__top.".$self->v_suffix;
@@ -979,7 +979,7 @@ sub compile {
 
     if ($param{atsim}) {
         $param{tool_define} ||= $param{atsim_define};
-        $self->_make_top();
+        $self->_make_top() if $param{make_top_shell};
         $self->_run(logfile=>"$self->{obj_dir}/atsim_compile.log",
                     fails=>$param{fails},
                     cmd=>[($ENV{VERILATOR_ATSIM}||"atsim"),
@@ -995,7 +995,7 @@ sub compile {
     elsif ($param{ghdl}) {
         $param{tool_define} ||= $param{ghdl_define};
         mkdir $self->{ghdl_work_dir};
-        $self->_make_top();
+        $self->_make_top() if $param{make_top_shell};
         $self->_run(logfile=>"$self->{obj_dir}/ghdl_compile.log",
                     fails=>$param{fails},
                     cmd=>[($ENV{VERILATOR_GHDL}||"ghdl"),
@@ -1013,7 +1013,7 @@ sub compile {
     }
     elsif ($param{vcs}) {
         $param{tool_define} ||= $param{vcs_define};
-        $self->_make_top();
+        $self->_make_top() if $param{make_top_shell};
         $self->_run(logfile=>"$self->{obj_dir}/vcs_compile.log",
                     fails=>$param{fails},
                     cmd=>[($ENV{VERILATOR_VCS}||"vcs"),
@@ -1029,7 +1029,7 @@ sub compile {
     }
     elsif ($param{nc}) {
         $param{tool_define} ||= $param{nc_define};
-        $self->_make_top();
+        $self->_make_top() if $param{make_top_shell};
         my @more_args;
         if ($self->vhdl) {
             ((my $ts = $param{top_shell_filename}) =~ s!\.v!!);
@@ -1051,7 +1051,7 @@ sub compile {
     }
     elsif ($param{ms}) {
         $param{tool_define} ||= $param{ms_define};
-        $self->_make_top();
+        $self->_make_top() if $param{make_top_shell};
         $self->_run(logfile=>"$self->{obj_dir}/ms_compile.log",
                     fails=>$param{fails},
                     cmd=>[("vlib $self->{obj_dir}/work && "),
@@ -1067,7 +1067,7 @@ sub compile {
     }
     elsif ($param{iv}) {
         $param{tool_define} ||= $param{iv_define};
-        $self->_make_top();
+        $self->_make_top() if $param{make_top_shell};
         my @cmd = (($ENV{VERILATOR_IVERILOG}||"iverilog"),
                    @{$param{iv_flags}},
                    @{$param{iv_flags2}},
@@ -1084,7 +1084,7 @@ sub compile {
     }
     elsif ($param{xsim}) {
         $param{tool_define} ||= $param{xsim_define};
-        $self->_make_top();
+        $self->_make_top() if $param{make_top_shell};
         $self->_run(logfile=>"$self->{obj_dir}/xsim_compile.log",
                     fails=>$param{fails},
                     cmd=>[($ENV{VERILATOR_XVLOG}||"xvlog"),