diff --git a/BUILDING.md b/BUILDING.md
index 9c1fb6899911c4..47630ddf150216 100644
--- a/BUILDING.md
+++ b/BUILDING.md
@@ -65,7 +65,7 @@ Depending on host platform, the selection of toolchains may vary.
 
 #### Unix
 
-* GCC 4.8.5 or newer
+* GCC 4.9.4 or newer
 * Clang 3.4.2 or newer
 
 #### Windows
@@ -80,8 +80,8 @@ Depending on host platform, the selection of toolchains may vary.
 
 Prerequisites:
 
-* `gcc` and `g++` 4.8.5 or newer, or
-* `clang` and `clang++` 3.4.2 or newer
+* `gcc` and `g++` 4.9.4 or newer, or
+* `clang` and `clang++` 3.4.2 or newer (macOS: latest Xcode Command Line Tools)
 * Python 2.6 or 2.7
 * GNU Make 3.81 or newer