findclasslist.pl: add a way to mark lines to be ignored

In case they get erroneously extracted. For example, in Core5Compat,
QTextCodec appears in the _p.h as a full class if !QT_CONFIG(textcodec)
(I don't know what that is for, but it's there).

Pick-to: 6.4
Change-Id: Ic6547f8247454b47baa8fffd170eb1d0f7e6d0f9
Reviewed-by: Jörg Bornemann <joerg.bornemann@qt.io>

mkspecs/features/data/unix/findclasslist.pl

@@ -18,6 +18,12 @@ while (<STDIN>) {
     open HDR, "<$1" or die("Could not open header $1: $!");
     my $comment = "    /* $1 */";
     while (my $line = <HDR>) {
+        if ($line =~ /\bELFVERSION:(\S+)\b/) {
+            last if $1 eq "stop";
+            <HDR> if $1 eq "ignore-next"; # load next line
+            next if $1 eq "ignore" or $1 eq "ignore-next";
+        }
+
         # Match a struct or class declaration, but not a forward declaration
         $line =~ /^(?:struct|class|namespace) (?:Q_.*_EXPORT)? (\w+)(?!;)/ or next;
         print $comment if $comment;

src/dbus/dbus_minimal_p.h

@@ -15,6 +15,8 @@
 // We mean it.
 //
 
+// These structures are not ours, so ELFVERSION:stop
+
 extern "C" {
 
 // Equivalent to dbus-arch-deps.h (generated from dbus-arch-deps.h.in)