1 files changed, 52 insertions, 0 deletions
diff --git a/src/deps/skia/include/private/SkSafe_math.h b/src/deps/skia/include/private/SkSafe_math.h
new file mode 100644
index 000000000..144b28a4a
--- /dev/null
+++ b/src/deps/skia/include/private/SkSafe_math.h
@@ -0,0 +1,52 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkSafe_math_DEFINED
+#define SkSafe_math_DEFINED
+
+// This file protects against known bugs in ucrt\math.h.
+// Namely, that header defines inline methods without marking them static,
+// which makes it very easy to cause ODR violations and ensuing chaos.
+//
+// TODO: other headers?  Here are some potential problem headers:
+// $ grep -R __inline * | grep -v static | cut -f 1 -d: | sort | uniq
+//   corecrt.h
+//   corecrt_stdio_config.h
+//   ctype.h
+//   fenv.h
+//   locale.h
+//   malloc.h
+//   math.h
+//   tchar.h
+//   wchar.h
+// I took a quick look through other headers outside math.h.
+// Nothing looks anywhere near as likely to be used by Skia as math.h.
+
+#if defined(_MSC_VER) && !defined(_INC_MATH)
+    // Our strategy here is to simply inject "static" into the headers
+    // where it should have been written, just before __inline.
+    //
+    // Most inline-but-not-static methods in math.h are 32-bit only,
+    // but not all of them (see frexpf, hypothf, ldexpf...).  So to
+    // be safe, 32- and 64-bit builds both get this treatment.
+
+    #define __inline static __inline
+    #include <math.h>
+    #undef __inline
+
+    #if !defined(_INC_MATH)
+        #error Hmm.  Looks like math.h has changed its header guards.
+    #endif
+
+    #define INC_MATH_IS_SAFE_NOW
+
+#else
+    #include <math.h>
+
+#endif
+
+#endif//SkSafe_math_DEFINED