diff --git a/crypto/perlasm/arm-xlate.pl b/crypto/perlasm/arm-xlate.pl
index abb97e3d..eb8ea59b 100755
--- a/crypto/perlasm/arm-xlate.pl
+++ b/crypto/perlasm/arm-xlate.pl
@@ -141,6 +141,9 @@ sub expand_line {
 }
 
 print <<___;
+// This file is generated from a similarly-named Perl script in the BoringSSL
+// source tree. Do not edit by hand.
+
 #if defined(__has_feature)
 #if __has_feature(memory_sanitizer) && !defined(OPENSSL_NO_ASM)
 #define OPENSSL_NO_ASM
diff --git a/crypto/perlasm/ppc-xlate.pl b/crypto/perlasm/ppc-xlate.pl
index 7f01dbde..0ce231f2 100644
--- a/crypto/perlasm/ppc-xlate.pl
+++ b/crypto/perlasm/ppc-xlate.pl
@@ -256,6 +256,9 @@ my $darn = sub {
 };
 
 print <<___;
+# This file is generated from a similarly-named Perl script in the BoringSSL
+# source tree. Do not edit by hand.
+
 #if defined(__has_feature)
 #if __has_feature(memory_sanitizer) && !defined(OPENSSL_NO_ASM)
 #define OPENSSL_NO_ASM
diff --git a/crypto/perlasm/x86_64-xlate.pl b/crypto/perlasm/x86_64-xlate.pl
index 3ec9b6c6..49551c81 100755
--- a/crypto/perlasm/x86_64-xlate.pl
+++ b/crypto/perlasm/x86_64-xlate.pl
@@ -1123,6 +1123,16 @@ my $endbranch = sub {
 
 ########################################################################
 
+{
+  my $comment = "#";
+  $comment = ";" if ($masm || $nasm);
+  print <<___;
+$comment This file is generated from a similarly-named Perl script in the BoringSSL
+$comment source tree. Do not edit by hand.
+
+___
+}
+
 if ($nasm) {
     print <<___;
 default	rel
diff --git a/crypto/perlasm/x86asm.pl b/crypto/perlasm/x86asm.pl
index 6a2755df..c9f645e0 100644
--- a/crypto/perlasm/x86asm.pl
+++ b/crypto/perlasm/x86asm.pl
@@ -255,9 +255,16 @@ sub ::asciz
 
 sub ::asm_finish
 {   &file_end();
-    print "#if defined(__i386__)\n" unless $win32;
+    my $comment = "#";
+    $comment = ";" if ($win32 || $netware);
+    print <<___;
+$comment This file is generated from a similarly-named Perl script in the BoringSSL
+$comment source tree. Do not edit by hand.
+
+___
+    print "#if defined(__i386__)\n" unless ($win32 || $netware);
     print @out;
-    print "#endif\n" unless $win32;
+    print "#endif\n" unless ($win32 || $netware);
 }
 
 sub ::asm_init