diff --git a/src/tools/msvc/Install.pm b/src/tools/msvc/Install.pm
index 0ea3ad041bc0566fbb8cb688d67c99566de6b938..3e32d019553d8d74ac79b95d6280d2fcf0237d48 100644
--- a/src/tools/msvc/Install.pm
+++ b/src/tools/msvc/Install.pm
@@ -58,8 +58,8 @@ sub Install
 
 		# suppress warning about harmless redeclaration of $config
 		no warnings 'misc';
-		require "config_default.pl";
-		require "config.pl" if (-f "config.pl");
+		do "config_default.pl";
+		do "config.pl" if (-f "config.pl");
 	}
 
 	chdir("../../..")    if (-f "../../../configure");
diff --git a/src/tools/msvc/build.pl b/src/tools/msvc/build.pl
index c4e4dc79a34a026e755200fc51743296c6e75c2e..dc9818cab6220e9257ef85c3578789c55cd409d3 100644
--- a/src/tools/msvc/build.pl
+++ b/src/tools/msvc/build.pl
@@ -21,17 +21,17 @@ use Mkvcbuild;
 
 if (-e "src/tools/msvc/buildenv.pl")
 {
-	require "src/tools/msvc/buildenv.pl";
+	do "src/tools/msvc/buildenv.pl";
 }
 elsif (-e "./buildenv.pl")
 {
-	require "./buildenv.pl";
+	do "./buildenv.pl";
 }
 
 # set up the project
 our $config;
-require "config_default.pl";
-require "config.pl" if (-f "src/tools/msvc/config.pl");
+do "config_default.pl";
+do "config.pl" if (-f "src/tools/msvc/config.pl");
 
 my $vcver = Mkvcbuild::mkvcbuild($config);
 
diff --git a/src/tools/msvc/builddoc.pl b/src/tools/msvc/builddoc.pl
index 2b56ced43ce2df123b19abf5a9cb44e8a5b937ca..e0b5c50b34242709bbebf4b53ec15ae59c69b3c4 100644
--- a/src/tools/msvc/builddoc.pl
+++ b/src/tools/msvc/builddoc.pl
@@ -18,7 +18,7 @@ chdir '../../..' if (-d '../msvc' && -d '../../../src');
 
 noversion() unless -e 'doc/src/sgml/version.sgml';
 
-require 'src/tools/msvc/buildenv.pl' if -e 'src/tools/msvc/buildenv.pl';
+do 'src/tools/msvc/buildenv.pl' if -e 'src/tools/msvc/buildenv.pl';
 
 my $docroot = $ENV{DOCROOT};
 die "bad DOCROOT '$docroot'" unless ($docroot && -d $docroot);
diff --git a/src/tools/msvc/install.pl b/src/tools/msvc/install.pl
index d7b7c7ee615a59f1339cc5eb9fcf7fdf5b4d57df..90425ca8fc68ebe70cfe41031f8c846d421ae67f 100755
--- a/src/tools/msvc/install.pl
+++ b/src/tools/msvc/install.pl
@@ -18,11 +18,11 @@ use Install qw(Install);
 
 if (-e "src/tools/msvc/buildenv.pl")
 {
-	require "src/tools/msvc/buildenv.pl";
+	do "src/tools/msvc/buildenv.pl";
 }
 elsif (-e "./buildenv.pl")
 {
-	require "./buildenv.pl";
+	do "./buildenv.pl";
 }
 
 my $target = shift || Usage();
diff --git a/src/tools/msvc/mkvcbuild.pl b/src/tools/msvc/mkvcbuild.pl
index 748b0eb41563b1ca786ffd745a181959b3d1059b..34e861375c00652c272e035806627bd922603a31 100644
--- a/src/tools/msvc/mkvcbuild.pl
+++ b/src/tools/msvc/mkvcbuild.pl
@@ -23,7 +23,7 @@ print "Warning: no config.pl found, using default.\n"
   unless (-f 'src/tools/msvc/config.pl');
 
 our $config;
-require 'src/tools/msvc/config_default.pl';
-require 'src/tools/msvc/config.pl' if (-f 'src/tools/msvc/config.pl');
+do 'src/tools/msvc/config_default.pl';
+do 'src/tools/msvc/config.pl' if (-f 'src/tools/msvc/config.pl');
 
 Mkvcbuild::mkvcbuild($config);
diff --git a/src/tools/msvc/pgbison.pl b/src/tools/msvc/pgbison.pl
index 31e75403f594f9e232e5e6e625dbaa4623693ad9..086a07ddf6632c44dc375755db44f3ae0da07133 100644
--- a/src/tools/msvc/pgbison.pl
+++ b/src/tools/msvc/pgbison.pl
@@ -7,7 +7,7 @@ use File::Basename;
 
 # assume we are in the postgres source root
 
-require 'src/tools/msvc/buildenv.pl' if -e 'src/tools/msvc/buildenv.pl';
+do 'src/tools/msvc/buildenv.pl' if -e 'src/tools/msvc/buildenv.pl';
 
 my ($bisonver) = `bison -V`;    # grab first line
 $bisonver = (split(/\s+/, $bisonver))[3];    # grab version number
diff --git a/src/tools/msvc/pgflex.pl b/src/tools/msvc/pgflex.pl
index 0410e3aa02b036d99d30537bf029374e9333dc1b..22b71ce2371b0d7c81d9002fec0744df40bd41cd 100644
--- a/src/tools/msvc/pgflex.pl
+++ b/src/tools/msvc/pgflex.pl
@@ -10,7 +10,7 @@ use File::Basename;
 
 # assume we are in the postgres source root
 
-require 'src/tools/msvc/buildenv.pl' if -e 'src/tools/msvc/buildenv.pl';
+do 'src/tools/msvc/buildenv.pl' if -e 'src/tools/msvc/buildenv.pl';
 
 my ($flexver) = `flex -V`;    # grab first line
 $flexver = (split(/\s+/, $flexver))[1];
diff --git a/src/tools/msvc/vcregress.pl b/src/tools/msvc/vcregress.pl
index b5699d1b45253390d1d94c677797c1e30bbad351..babe74636691c44145342543f31c985d8d3fb947 100644
--- a/src/tools/msvc/vcregress.pl
+++ b/src/tools/msvc/vcregress.pl
@@ -22,8 +22,8 @@ chdir "../../.." if (-d "../../../src/tools/msvc");
 my $topdir = getcwd();
 my $tmp_installdir = "$topdir/tmp_install";
 
-require 'src/tools/msvc/config_default.pl';
-require 'src/tools/msvc/config.pl' if (-f 'src/tools/msvc/config.pl');
+do 'src/tools/msvc/config_default.pl';
+do 'src/tools/msvc/config.pl' if (-f 'src/tools/msvc/config.pl');
 
 # buildenv.pl is for specifying the build environment settings
 # it should contain lines like:
@@ -31,7 +31,7 @@ require 'src/tools/msvc/config.pl' if (-f 'src/tools/msvc/config.pl');
 
 if (-e "src/tools/msvc/buildenv.pl")
 {
-	require "src/tools/msvc/buildenv.pl";
+	do "src/tools/msvc/buildenv.pl";
 }
 
 my $what = shift || "";