From f6cbe2e4d3975101b5319f731dee8bd1efca5a22 Mon Sep 17 00:00:00 2001
From: handa <handa>
Date: Fri, 24 Jun 2005 02:13:10 +0000
Subject: [PATCH] (OTF_check_features): If the MSB of a feature tag is set,
 treat it as a negation flag.

---
 src/otfopen.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/src/otfopen.c b/src/otfopen.c
index b9e93fd..b484003 100644
--- a/src/otfopen.c
+++ b/src/otfopen.c
@@ -2955,13 +2955,23 @@ OTF_check_features (OTF *otf, int gsubp,
   for (j = 0; j < n_features; j++)
     {
       OTF_Tag feature = features[j];
+      int negate = 0;
 
       if (feature == 0)
 	continue;
+      if (((unsigned) feature) & 0x80000000)
+	{
+	  feature = (OTF_Tag) (((unsigned) feature) & 0x7FFFFFFF);
+	  negate = 1;
+	}
       for (i = 0; i < LangSys->FeatureCount; i++)
 	if (feature_list->Feature[LangSys->FeatureIndex[i]].FeatureTag
 	    == feature)
-	  break;
+	  {
+	    if (negate)
+	      return 0;
+	    break;
+	  }
       if (i == LangSys->FeatureCount)
 	return 0;
     }
-- 
1.7.10.4