1 files changed, 57 insertions, 0 deletions
diff --git a/gfx/layers/BuildConstants.h b/gfx/layers/BuildConstants.h
new file mode 100644
index 0000000000..6db150d136
--- /dev/null
+++ b/gfx/layers/BuildConstants.h
@@ -0,0 +1,57 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef BUILD_CONSTANTS_H_
+#define BUILD_CONSTANTS_H_
+
+/**
+ * Why not just use ifdefs?
+ * ifdefs tend to result in code that compiles on one platform but not another.
+ * Given the number of build and platform configurations we have, it's best to
+ * aim to compile the same on as many platforms as possible, and let the
+ * compiler see the constexprs and handle dead-code elision itself.
+ */
+
+namespace mozilla {
+
+constexpr bool kIsDebug =
+#ifdef DEBUG
+    true;
+#else
+    false;
+#endif
+
+constexpr bool kIsWindows =
+#ifdef XP_WIN
+    true;
+#else
+    false;
+#endif
+
+constexpr bool kIsMacOS =
+#ifdef XP_MACOSX
+    true;
+#else
+    false;
+#endif
+
+constexpr bool kIsLinux =
+#ifdef MOZ_WIDGET_GTK
+    true;
+#else
+    false;
+#endif
+
+constexpr bool kIsAndroid =
+#ifdef MOZ_WIDGET_ANDROID
+    true;
+#else
+    false;
+#endif
+
+}  // namespace mozilla
+
+#endif  // BUILD_CONSTANTS_H_