Fix warnings

Part of https://github.com/behdad/harfbuzz/pull/68
diff --git a/src/hb-ot-font.cc b/src/hb-ot-font.cc
index 2af2f54..f6f979d 100644
--- a/src/hb-ot-font.cc
+++ b/src/hb-ot-font.cc
@@ -45,9 +45,9 @@
 
   inline void init (hb_face_t *face,
 		    hb_tag_t _hea_tag, hb_tag_t _mtx_tag,
-		    unsigned int default_advance)
+		    unsigned int default_advance_)
   {
-    this->default_advance = default_advance;
+    this->default_advance = default_advance_;
     this->num_metrics = face->get_num_glyphs ();
 
     hb_blob_t *_hea_blob = OT::Sanitizer<OT::_hea>::sanitize (face->reference_table (_hea_tag));
diff --git a/src/hb-ot-layout-gsubgpos-private.hh b/src/hb-ot-layout-gsubgpos-private.hh
index cbc6840..842be88 100644
--- a/src/hb-ot-layout-gsubgpos-private.hh
+++ b/src/hb-ot-layout-gsubgpos-private.hh
@@ -516,39 +516,39 @@
   inline bool
   match_properties_mark (hb_codepoint_t  glyph,
 			 unsigned int    glyph_props,
-			 unsigned int    lookup_props) const
+			 unsigned int    match_props) const
   {
     /* If using mark filtering sets, the high short of
-     * lookup_props has the set index.
+     * match_props has the set index.
      */
-    if (lookup_props & LookupFlag::UseMarkFilteringSet)
-      return gdef.mark_set_covers (lookup_props >> 16, glyph);
+    if (match_props & LookupFlag::UseMarkFilteringSet)
+      return gdef.mark_set_covers (match_props >> 16, glyph);
 
-    /* The second byte of lookup_props has the meaning
+    /* The second byte of match_props has the meaning
      * "ignore marks of attachment type different than
      * the attachment type specified."
      */
-    if (lookup_props & LookupFlag::MarkAttachmentType)
-      return (lookup_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType);
+    if (match_props & LookupFlag::MarkAttachmentType)
+      return (match_props & LookupFlag::MarkAttachmentType) == (glyph_props & LookupFlag::MarkAttachmentType);
 
     return true;
   }
 
   inline bool
   check_glyph_property (const hb_glyph_info_t *info,
-			unsigned int  lookup_props) const
+			unsigned int  match_props) const
   {
     hb_codepoint_t glyph = info->codepoint;
     unsigned int glyph_props = _hb_glyph_info_get_glyph_props (info);
 
     /* Not covered, if, for example, glyph class is ligature and
-     * lookup_props includes LookupFlags::IgnoreLigatures
+     * match_props includes LookupFlags::IgnoreLigatures
      */
-    if (glyph_props & lookup_props & LookupFlag::IgnoreFlags)
+    if (glyph_props & match_props & LookupFlag::IgnoreFlags)
       return false;
 
     if (unlikely (glyph_props & HB_OT_LAYOUT_GLYPH_PROPS_MARK))
-      return match_properties_mark (glyph, glyph_props, lookup_props);
+      return match_properties_mark (glyph, glyph_props, match_props);
 
     return true;
   }