From 702b62657065bbf0fa7f58ce843100d6e6681370 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dani=C3=ABl=20de=20Kok?= <me@danieldk.eu>
Date: Fri, 6 Nov 2020 09:55:12 +0100
Subject: [PATCH 1/2] mkl: Fix pkg-config file

There was a spurious `intel64` in some library paths.
---
 pkgs/development/libraries/science/math/mkl/default.nix | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/pkgs/development/libraries/science/math/mkl/default.nix b/pkgs/development/libraries/science/math/mkl/default.nix
index 2be3baed4497..7cbc50bc5b37 100644
--- a/pkgs/development/libraries/science/math/mkl/default.nix
+++ b/pkgs/development/libraries/science/math/mkl/default.nix
@@ -90,7 +90,8 @@ in stdenvNoCC.mkDerivation {
       substituteInPlace $f \
         --replace "prefix=<INSTALLDIR>/mkl" "prefix=$out" \
         --replace $\{MKLROOT} "$out" \
-        --replace "lib/intel64_lin" "lib"
+        --replace "lib/intel64_lin" "lib" \
+        --replace "lib/intel64" "lib"
     done
 
     for f in $(find opt/intel -name 'mkl*iomp.pc') ; do

From b5d27eb87c99a476460f5bec2a636848a4e7cef6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dani=C3=ABl=20de=20Kok?= <me@danieldk.eu>
Date: Fri, 6 Nov 2020 09:56:13 +0100
Subject: [PATCH 2/2] mkl: Add a small test program

The MKL pkg-config files often change and are then incorrect for our
paths. pkg-config validation finds some issues, but not incorrect
paths. So, add a small test program to test whether the generated
pkg-config files can actually be used to build a functioning
binary. Hopefully this catches future regressions.
---
 .../libraries/science/math/mkl/default.nix    |  5 ++-
 .../science/math/mkl/test/default.nix         | 33 +++++++++++++++++++
 .../libraries/science/math/mkl/test/test.c    | 12 +++++++
 3 files changed, 49 insertions(+), 1 deletion(-)
 create mode 100644 pkgs/development/libraries/science/math/mkl/test/default.nix
 create mode 100644 pkgs/development/libraries/science/math/mkl/test/test.c

diff --git a/pkgs/development/libraries/science/math/mkl/default.nix b/pkgs/development/libraries/science/math/mkl/default.nix
index 7cbc50bc5b37..7b91940033dd 100644
--- a/pkgs/development/libraries/science/math/mkl/default.nix
+++ b/pkgs/development/libraries/science/math/mkl/default.nix
@@ -1,4 +1,5 @@
-{ stdenvNoCC
+{ callPackage
+, stdenvNoCC
 , fetchurl
 , rpmextract
 , undmg
@@ -157,6 +158,8 @@ in stdenvNoCC.mkDerivation {
   dontStrip = true;
   dontPatchELF = true;
 
+  passthru.tests.pkg-config = callPackage ./test { };
+
   meta = with stdenvNoCC.lib; {
     description = "Intel Math Kernel Library";
     longDescription = ''
diff --git a/pkgs/development/libraries/science/math/mkl/test/default.nix b/pkgs/development/libraries/science/math/mkl/test/default.nix
new file mode 100644
index 000000000000..688c0ec7c399
--- /dev/null
+++ b/pkgs/development/libraries/science/math/mkl/test/default.nix
@@ -0,0 +1,33 @@
+{ stdenv, pkg-config, mkl }:
+
+stdenv.mkDerivation {
+  pname = "mkl-test";
+  version = mkl.version;
+
+  src = ./.;
+
+  nativeBuildInputs = [ pkg-config ];
+
+  buildInputs = [ mkl ];
+
+  doCheck = true;
+
+  buildPhase = ''
+    # Check regular Nix build.
+    gcc $(pkg-config --cflags --libs mkl-dynamic-ilp64-seq) test.c -o test
+
+    # Clear flags to ensure that we are purely relying on options
+    # provided by pkg-config.
+    NIX_CFLAGS_COMPILE="" \
+    NIX_LDFLAGS="" \
+      gcc $(pkg-config --cflags --libs mkl-dynamic-ilp64-seq) test.c -o test
+  '';
+
+  installPhase = ''
+    touch $out
+  '';
+
+  checkPhase = ''
+    ./test
+  '';
+}
diff --git a/pkgs/development/libraries/science/math/mkl/test/test.c b/pkgs/development/libraries/science/math/mkl/test/test.c
new file mode 100644
index 000000000000..9413ac0c68e9
--- /dev/null
+++ b/pkgs/development/libraries/science/math/mkl/test/test.c
@@ -0,0 +1,12 @@
+#include <assert.h>
+
+#include <mkl_cblas.h>
+
+int main() {
+  float u[] = {1., 2., 3.};
+  float v[] = {4., 5., 6.};
+
+  float dp = cblas_sdot(3, u, 1, v, 1);
+
+  assert(dp == 32.);
+}