diff --git a/ANNOUNCE b/ANNOUNCE
index cac93df67..924de188d 100644
--- a/ANNOUNCE
+++ b/ANNOUNCE
@@ -1411,6 +1411,12 @@ Version 1.7.0beta84 [September 26, 2016]
 Version 1.7.0beta85 [December 27, 2016]
   Updated the documentation about CRC and ADLER32 handling.
   Quieted warnings from clang-3.8 in pngunknown.c and pngvalid.c.
+  Removed the use of a macro containing the pre-processor 'defined'
+    operator.  It is unclear whether this is valid; a macro that
+    "generates" 'defined' is not permitted, but the use of the word
+    "generates" within the C90 standard seems to imply more than simple
+    substitution of an expression itself containing a well-formed defined
+    operation.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
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diff --git a/CHANGES b/CHANGES
index f8df5c798..1d6e1cc1c 100644
--- a/CHANGES
+++ b/CHANGES
@@ -5711,6 +5711,12 @@ Version 1.7.0beta84 [September 26, 2016]
 Version 1.7.0beta85 [December 27, 2016]
   Updated the documentation about CRC and ADLER32 handling.
   Quieted warnings from clang-3.8 in pngunknown.c and pngvalid.c.
+  Removed the use of a macro containing the pre-processor 'defined'
+    operator.  It is unclear whether this is valid; a macro that
+    "generates" 'defined' is not permitted, but the use of the word
+    "generates" within the C90 standard seems to imply more than simple
+    substitution of an expression itself containing a well-formed defined
+    operation.
 
 Send comments/corrections/commendations to png-mng-implement at lists.sf.net
 (subscription required; visit
diff --git a/contrib/libtests/pngvalid.c b/contrib/libtests/pngvalid.c
index 1c45b615a..b0b75b94b 100644
--- a/contrib/libtests/pngvalid.c
+++ b/contrib/libtests/pngvalid.c
@@ -1,9 +1,8 @@
 
 /* pngvalid.c - validate libpng by constructing then reading png files.
  *
- * Last changed in libpng 1.6.26 [(PENDING RELEASE)]
- * Copyright (c) 2014-2016 Glenn Randers-Pehrson
- * Written by John Cunningham Bowler
+ * Last changed in libpng 1.6.27 [(PENDING RELEASE)]
+ * Copyright (c) 2014-2016 John Cunningham Bowler
  *
  * This code is released under the libpng license.
  * For conditions of distribution and use, see the disclaimer
@@ -4011,8 +4010,11 @@ check_interlace_type(int const interlace_type)
 #  define do_own_interlace 1
 #endif /* WRITE_INTERLACING tests */
 
-#define CAN_WRITE_INTERLACE\
-   PNG_LIBPNG_VER >= 10700 || defined PNG_WRITE_INTERLACING_SUPPORTED
+#if PNG_LIBPNG_VER >= 10700 || defined PNG_WRITE_INTERLACING_SUPPORTED
+#   define CAN_WRITE_INTERLACE 1
+#else
+#   define CAN_WRITE_INTERLACE 0
+#endif
 
 /* Do the same thing for read interlacing; this controls whether read tests do
  * their own de-interlace or use libpng.