Merge branch 'master' into staging

1 files changed, 16 insertions, 5 deletions

diff --git a/doc/languages-frameworks/python.section.md b/doc/languages-frameworks/python.section.md
index eefe46b15de1..acd2bf769b0d 100644
--- a/doc/languages-frameworks/python.section.md
+++ b/doc/languages-frameworks/python.section.md
@@ -484,10 +484,12 @@ and in this case the `python35` interpreter is automatically used.
 ### Interpreters
 
 Versions 2.7, 3.5, 3.6 and 3.7 of the CPython interpreter are available as
-respectively `python27`, `python35`, `python36`, and `python37`. The PyPy
-interpreter is available as `pypy`. The aliases `python2` and `python3`
-correspond to respectively `python27` and `python37`. The default interpreter,
-`python`, maps to `python2`. The Nix expressions for the interpreters can be
+respectively `python27`, `python35`, `python36` and `python37`. The aliases
+`python2` and `python3` correspond to respectively `python27` and
+`python37`. The default interpreter, `python`, maps to `python2`. The PyPy
+interpreters compatible with Python 2.7 and 3 are available as `pypy27` and
+`pypy3`, with aliases `pypy2` mapping to `pypy27` and `pypy` mapping to
+`pypy2`. The Nix expressions for the interpreters can be
 found in `pkgs/development/interpreters/python`.
 
 All packages depending on any Python interpreter get appended
@@ -1102,7 +1104,7 @@ on `numpy` will be built with `mkl`.
 The following is an overlay that configures `numpy` to use `mkl`:
 ```nix
 self: super: {
-  python36 = super.python36.override {
+  python37 = super.python37.override {
     packageOverrides = python-self: python-super: {
       numpy = python-super.numpy.override {
         blas = super.pkgs.mkl;
@@ -1112,6 +1114,15 @@ self: super: {
 }
 ```
 
+`mkl` requires an `openmp` implementation when running with multiple processors.
+By default, `mkl` will use Intel's `iomp` implementation if no other is
+specified, but this is a runtime-only dependency and binary compatible with the
+LLVM implementation. To use that one instead, Intel recommends users set it with
+`LD_PRELOAD`.
+
+Note that `mkl` is only available on `x86_64-{linux,darwin}` platforms;
+moreover, Hydra is not building and distributing pre-compiled binaries using it.
+
 ## Contributing
 
 ### Contributing guidelines