diff --git a/ANNOUNCE b/ANNOUNCE
index d9774c8de..8229de227 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -48,6 +48,7 @@ Version 1.6.9beta02 [December 28, 2013]
   Merged with pngvalid.c from libpng-1.7 changes to create a single
     pngvalid.c
   Removed #error macro from contrib/tools/pngfix.c (Thomas Klausner).
+  Merged pngrio.c, pngtrans.c, pngwio.c, and pngerror.c with libpng-1.7.0
 
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diff --git a/CHANGES b/CHANGES
index cd08f4f58..92d3c634e 100644
--- a/CHANGES
+++ b/CHANGES
@@ -4773,6 +4773,7 @@ Version 1.6.9beta02 [December 28, 2013]
   Merged with pngvalid.c from libpng-1.7 changes to create a single
     pngvalid.c
   Removed #error macro from contrib/tools/pngfix.c (Thomas Klausner).
+  Merged pngrio.c, pngtrans.c, pngwio.c, and pngerror.c with libpng-1.7.0
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/pngerror.c b/pngerror.c
index b46d28f19..3faf27319 100644
--- a/pngerror.c
+++ b/pngerror.c
@@ -761,7 +761,12 @@ png_longjmp,(png_const_structrp png_ptr, int val),PNG_NORETURN)
       png_ptr->longjmp_fn(*png_ptr->jmp_buf_ptr, val);
 #endif
 
-   /* Here if not setjmp support or if png_ptr is null. */
+   /* If control reaches this point, png_longjmp() must not return. The only
+    * choice is to terminate the whole process (or maybe the thread); to do
+    * this the ANSI-C abort() function is used unless a different method is 
+    * implemented by overriding the default configuration setting for
+    * PNG_ABORT().
+    */
    PNG_ABORT();
 }
 
diff --git a/pngrio.c b/pngrio.c
index d7864407b..57379e1fb 100644
--- a/pngrio.c
+++ b/pngrio.c
@@ -1,7 +1,7 @@
 
 /* pngrio.c - functions for data input
  *
- * Last changed in libpng 1.6.0 [February 14, 2013]
+ * Last changed in libpng 1.6.9 [(PENDING RELEASE)]
  * Copyright (c) 1998-2013 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.)
@@ -102,6 +102,7 @@ png_set_read_fn(png_structrp png_ptr, png_voidp io_ptr,
    png_ptr->read_data_fn = read_data_fn;
 #endif
 
+#ifdef PNG_WRITE_SUPPORTED
    /* It is an error to write to a read device */
    if (png_ptr->write_data_fn != NULL)
    {
@@ -110,6 +111,7 @@ png_set_read_fn(png_structrp png_ptr, png_voidp io_ptr,
           "Can't set both read_data_fn and write_data_fn in the"
           " same structure");
    }
+#endif
 
 #ifdef PNG_WRITE_FLUSH_SUPPORTED
    png_ptr->output_flush_fn = NULL;
diff --git a/pngtrans.c b/pngtrans.c
index 8f8bc5d9e..108beeed0 100644
--- a/pngtrans.c
+++ b/pngtrans.c
@@ -1,7 +1,7 @@
 
 /* pngtrans.c - transforms the data in a row (used by both readers and writers)
  *
- * Last changed in libpng 1.6.2 [April 25, 2013]
+ * Last changed in libpng 1.6.9 [(PENDING RELEASE)]
  * Copyright (c) 1998-2013 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.)
@@ -57,7 +57,9 @@ png_set_packing(png_structrp png_ptr)
    if (png_ptr->bit_depth < 8)
    {
       png_ptr->transformations |= PNG_PACK;
-      png_ptr->usr_bit_depth = 8;
+#     ifdef PNG_WRITE_SUPPORTED
+         png_ptr->usr_bit_depth = 8;
+#     endif
    }
 }
 #endif
diff --git a/pngwio.c b/pngwio.c
index 4581b0802..430937348 100644
--- a/pngwio.c
+++ b/pngwio.c
@@ -1,7 +1,7 @@
 
 /* pngwio.c - functions for data output
  *
- * Last changed in libpng 1.6.8 [December 19, 2013]
+ * Last changed in libpng 1.6.9 [(PENDING RELEASE)]
  * Copyright (c) 1998-2013 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.)
@@ -153,6 +153,7 @@ png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
    PNG_UNUSED(output_flush_fn)
 #endif /* PNG_WRITE_FLUSH_SUPPORTED */
 
+#ifdef PNG_READ_SUPPORTED
    /* It is an error to read while writing a png file */
    if (png_ptr->read_data_fn != NULL)
    {
@@ -162,5 +163,6 @@ png_set_write_fn(png_structrp png_ptr, png_voidp io_ptr,
           "Can't set both read_data_fn and write_data_fn in the"
           " same structure");
    }
+#endif
 }
 #endif /* PNG_WRITE_SUPPORTED */