From c04eb7be9dd17ffc5dfbc9e2b31687f0a1b54ab1 Mon Sep 17 00:00:00 2001
From: James Zern <jzern@google.com>
Date: Thu, 3 May 2012 16:59:13 -0700
Subject: [PATCH] tcoder.c: define NOT_HAVE_LOG2 for MSVC builds

no version of msvc currently implements log2(). unconditionally define
NOT_HAVE_LOG2 in this case to simplify building libwebp sources in other
projects.

Change-Id: Ia9d985b1125553c5a8271d7e539bc1b4f898d749
---
 src/utils/tcoder.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/utils/tcoder.c b/src/utils/tcoder.c
index e319443a..035fa1f9 100644
--- a/src/utils/tcoder.c
+++ b/src/utils/tcoder.c
@@ -88,6 +88,10 @@
 extern "C" {
 #endif
 
+#if defined(_MSC_VER) && !defined(NOT_HAVE_LOG2)
+# define NOT_HAVE_LOG2 1
+#endif
+
 #ifdef NOT_HAVE_LOG2
 static double log2(double d) {
   const double kLog2Reciprocal = 1.442695040888963;