update compiler version in docs (#5281)

diff --git a/docs/install/from_source.rst b/docs/install/from_source.rst
index 7fa4898..12403a0 100644 (file)
--- a/docs/install/from_source.rst
+++ b/docs/install/from_source.rst
@@ -63,7 +63,7 @@ Our goal is to build the shared libraries:
 
 The minimal building requirements are
 
-- A recent c++ compiler supporting C++ 11 (g++-4.8 or higher)
+- A recent c++ compiler supporting C++ 14 (g++-5 or higher)
 - CMake 3.5 or higher
 - We highly recommend to build with LLVM to enable all the features.
 - If you want to use CUDA, CUDA toolkit version >= 8.0 is required. If you are upgrading from an older version, make sure you purge the older version and reboot after installation.