Enforces intel icpc >= 2017, fixes #1121 (#1363)

diff --git a/docs/changelog.rst b/docs/changelog.rst
index 2397056..2d9b452 100644
--- a/docs/changelog.rst
+++ b/docs/changelog.rst
@@ -21,6 +21,10 @@
 * The ``value()``  method of ``py::enum_`` now accepts an optional docstring
   that will be shown in the documentation of the associated enumeration.
 
+* Intel compilers have needed to be >= 17.0 since v2.1. Now the check
+  is explicit and a compile-time error is raised if the compiler does
+  not meet the requirements.
+
 v2.2.2 (February 7, 2018)
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