Script to detect unused autoconf outputs

Should help speed up mingw builds by a percent or two.

2 files changed, 23 insertions, 0 deletions

diff --git a/scripts/README b/scripts/README
index f2cb5013c..70c763923 100644
--- a/scripts/README
+++ b/scripts/README
@@ -6,6 +6,9 @@ Code maintenance scripts
 
 maint/checkLogs.pl -- Verify that Tor log statements are unique.
 
+maint/check_config_macros.pl -- Look for autoconf tests whose results are
+never used.
+
 maint/checkOptionDocs.pl -- Make sure that Tor options are documented in the
 manpage, and that the manpage only documents real Tor options.
 
diff --git a/scripts/maint/check_config_macros.pl b/scripts/maint/check_config_macros.pl
new file mode 100755
index 000000000..bcde2becc
--- /dev/null
+++ b/scripts/maint/check_config_macros.pl
@@ -0,0 +1,20 @@
+#!/usr/bin/perl -w
+
+use strict;
+
+my @macros = ();
+
+open(F, 'orconfig.h.in');
+while(<F>) {
+    if (/^#undef +([A-Za-z0-9_]*)/) {
+	push @macros, $1;
+    }
+}
+close F;
+
+for my $m (@macros) {
+    my $s = `git grep '$m' src`;
+    if ($s eq '') {
+	print "Unused: $m\n";
+    }
+}