From d83e9c95738df2e9f912c239201f50e53e40810b Mon Sep 17 00:00:00 2001
From: Matthew Bauer <mjbauer95@gmail.com>
Date: Tue, 31 Mar 2020 14:53:02 -0400
Subject: [PATCH] setup-hooks/audit-blas.sh: init

Add a simple hook that makes sure blas and lapack are linked to the
right place.
---
 pkgs/build-support/setup-hooks/audit-blas.sh | 37 ++++++++++++++++++++
 pkgs/top-level/all-packages.nix              |  4 +++
 2 files changed, 41 insertions(+)
 create mode 100644 pkgs/build-support/setup-hooks/audit-blas.sh

diff --git a/pkgs/build-support/setup-hooks/audit-blas.sh b/pkgs/build-support/setup-hooks/audit-blas.sh
new file mode 100644
index 000000000000..6a40073fb234
--- /dev/null
+++ b/pkgs/build-support/setup-hooks/audit-blas.sh
@@ -0,0 +1,37 @@
+# Ensure that we are always linking against “libblas.so.3” and
+# “liblapack.so.3”.
+
+auditBlas() {
+    local dir="$prefix"
+    [ -e "$dir" ] || return 0
+
+    local i
+    while IFS= read -r -d $'\0' i; do
+        if ! isELF "$i"; then continue; fi
+
+        if $OBJDUMP -p "$i" | grep 'NEEDED' | awk '{ print $2; }' | grep -q '\(libmkl_rt.so\|libopenblas.so.0\)'; then
+            echo "$i refers to a specific implementation of BLAS or LAPACK."
+            echo "This prevents users from switching BLAS/LAPACK implementations."
+            echo "Add \`blas' or \`lapack' to buildInputs instead of \`mkl' or \`openblas'."
+            exit 1
+        fi
+
+        (IFS=:
+         for dir in "$(patchelf --print-rpath "$i")"; do
+             if [ -f "$dir/libblas.so.3" ] || [ -f "$dir/libblas.so" ]; then
+                 if [ "$dir" != "@blas@/lib" ]; then
+                     echo "$dir is not allowed to contain a library named libblas.so.3"
+                     exit 1
+                 fi
+             fi
+             if [ -f "$dir/liblapack.so.3" ] || [ -f "$dir/liblapack.so" ]; then
+                 if [ "$dir" != "@lapack@/lib" ]; then
+                     echo "$dir is not allowed to contain a library named liblapack.so.3"
+                     exit 1
+                 fi
+             fi
+         done)
+    done < <(find "$dir" -type f -print0)
+}
+
+fixupOutputHooks+=(auditBlas)
diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 3c9d5274abde..37e000a25d78 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -104,6 +104,10 @@ in
 
   ### BUILD SUPPORT
 
+  auditBlasHook = makeSetupHook
+    { name = "auto-blas-hook"; deps = [ blas lapack ]; }
+    ../build-support/setup-hooks/audit-blas.sh;
+
   autoreconfHook = makeSetupHook
     { deps = [ autoconf automake gettext libtool ]; }
     ../build-support/setup-hooks/autoreconf.sh;