diff --git a/ANNOUNCE b/ANNOUNCE
index e721267e7..fd912bf80 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1,4 +1,4 @@
-Libpng 1.6.19beta01 - July 26, 2015
+Libpng 1.6.19beta01 - July 29, 2015
 
 This is not intended to be a public release.  It will be replaced
 within a few weeks by a public version or by another test version.
@@ -25,13 +25,18 @@ Other information:
 
 Changes since the last public release (1.6.18):
 
-Version 1.6.19beta01 [July 26, 2015]
+Version 1.6.19beta01 [July 29, 2015]
 
   Updated obsolete information about the simplified API macros in the
     manual pages (Bug report by Arc Riley).
   Avoid potentially dereferencing NULL info_ptr in png_info_init_3().
   Rearranged png.h to put the major sections in the same order as
     in libpng17.
+  Eliminated unused PNG_COST_SHIFT, PNG_WEIGHT_SHIFT, PNG_COST_FACTOR, and
+    PNG_WEIGHT_FACTOR macros.
+  Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
+    (Bug report by Viktor Szaka'ts).  Several warnings remain and are
+    unavoidable, where we test for overflow.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/CHANGES b/CHANGES
index c9d6ed1b9..733a7c835 100644
--- a/CHANGES
+++ b/CHANGES
@@ -5305,12 +5305,17 @@ Version 1.6.18rc03 [July 15, 2015]
 Version 1.6.18 [July 23, 2015]
   No changes.
 
-Version 1.6.19beta01 [July 26, 2015]
+Version 1.6.19beta01 [July 29, 2015]
   Updated obsolete information about the simplified API macros in the
     manual pages (Bug report by Arc Riley).
   Avoid potentially dereferencing NULL info_ptr in png_info_init_3().
   Rearranged png.h to put the major sections in the same order as
     in libpng17.
+  Eliminated unused PNG_COST_SHIFT, PNG_WEIGHT_SHIFT, PNG_COST_FACTOR, and
+    PNG_WEIGHT_FACTOR macros.
+  Suppressed some warnings from the Borland C++ 5.5.1/5.82 compiler
+    (Bug report by Viktor Szaka'ts).  Several warnings remain and are
+    unavoidable, where we test for overflow.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/png.c b/png.c
index 82ec7da50..e2e61a33f 100644
--- a/png.c
+++ b/png.c
@@ -1,7 +1,7 @@
 
 /* png.c - location for general purpose libpng functions
  *
- * Last changed in libpng 1.6.18 [July 23, 2015]
+ * Last changed in libpng 1.6.19 [(PENDING RELEASE)]
  * Copyright (c) 1998-2015 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -724,6 +724,7 @@ png_convert_to_rfc1123_buffer(char out[29], png_const_timep ptime)
       APPEND(':');
       APPEND_NUMBER(PNG_NUMBER_FORMAT_02u, (unsigned)ptime->second);
       APPEND_STRING(" +0000"); /* This reliably terminates the buffer */
+      PNG_UNUSED (pos)
 
 #     undef APPEND
 #     undef APPEND_NUMBER
@@ -768,13 +769,13 @@ png_get_copyright(png_const_structrp png_ptr)
 #else
 #  ifdef __STDC__
    return PNG_STRING_NEWLINE \
-      "libpng version 1.6.19beta01 - July 25, 2015" PNG_STRING_NEWLINE \
+      "libpng version 1.6.19beta01 - July 29, 2015" PNG_STRING_NEWLINE \
       "Copyright (c) 1998-2015 Glenn Randers-Pehrson" PNG_STRING_NEWLINE \
       "Copyright (c) 1996-1997 Andreas Dilger" PNG_STRING_NEWLINE \
       "Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc." \
       PNG_STRING_NEWLINE;
 #  else
-   return "libpng version 1.6.19beta01 - July 25, 2015\
+   return "libpng version 1.6.19beta01 - July 29, 2015\
       Copyright (c) 1998-2015 Glenn Randers-Pehrson\
       Copyright (c) 1996-1997 Andreas Dilger\
       Copyright (c) 1995-1996 Guy Eric Schalnat, Group 42, Inc.";
diff --git a/pngrutil.c b/pngrutil.c
index 8f8edbc58..1646dd2fc 100644
--- a/pngrutil.c
+++ b/pngrutil.c
@@ -1,7 +1,7 @@
 
 /* pngrutil.c - utilities to read a PNG file
  *
- * Last changed in libpng 1.6.18 [July 23, 2015]
+ * Last changed in libpng 1.6.19 [(PENDING RELEASE)]
  * Copyright (c) 1998-2015 Glenn Randers-Pehrson
  * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
  * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
@@ -1818,7 +1818,7 @@ png_handle_tRNS(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
          return;
       }
 
-      if (length > png_ptr->num_palette ||
+      if (length > (unsigned int) png_ptr->num_palette ||
          length > (unsigned int) PNG_MAX_PALETTE_LENGTH ||
          length == 0)
       {
@@ -1982,7 +1982,8 @@ png_handle_hIST(png_structrp png_ptr, png_inforp info_ptr, png_uint_32 length)
 
    num = length / 2 ;
 
-   if (num != png_ptr->num_palette || num > (unsigned int) PNG_MAX_PALETTE_LENGTH)
+   if (num != (unsigned int) png_ptr->num_palette ||
+       num > (unsigned int) PNG_MAX_PALETTE_LENGTH)
    {
       png_crc_finish(png_ptr, length);
       png_chunk_benign_error(png_ptr, "invalid");