diff --git a/doc/setup.rst b/doc/setup.rst
index f5f4c2d..4083fe6 100644
--- a/doc/setup.rst
+++ b/doc/setup.rst
@@ -8,7 +8,7 @@ The library is supported on Linux, OS X, FreeBSD, and Windows.
 
 The following compilers are supported to compile both the library and the tests:
 
-* GCC 4.9+
+* GCC 4.9+ (Can be relaxed to GCC 4.6+ when not using C++)
 * Clang 3.4+
 * MSVC 14+ (Included in Visual Studio 2015 or later)