stdenv: Put moving docs to $out/share in a separate setup hook

pkgs/build-support/setup-hooks/move-docs.sh

@@ -0,0 +1,24 @@
+# This setup hook automatically moves $out/{man,doc,info} to
+# $out/share.
+
+preFixupHooks+=(_moveDocs)
+
+_moveDocs() {
+    forceShare=${forceShare:=man doc info}
+    if [ -z "$forceShare" ]; then return; fi
+
+    for d in $forceShare; do
+        if [ -d "$prefix/$d" ]; then
+            if [ -d "$prefix/share/$d" ]; then
+                echo "both $d/ and share/$d/ exist!"
+            else
+                echo "moving $prefix/$d to $prefix/share/$d"
+                mkdir -p $prefix/share
+                if [ -w $prefix/share ]; then
+                    mv $prefix/$d $prefix/share
+                    ln -s share/$d $prefix
+                fi
+            fi
+        fi
+    done
+}

pkgs/stdenv/generic/default.nix

@@ -30,7 +30,8 @@ let
   unsafeGetAttrPos = builtins.unsafeGetAttrPos or (n: as: null);
 
   extraBuildInputs' = extraBuildInputs ++
-    [ ../../build-support/setup-hooks/compress-man-pages.sh
+    [ ../../build-support/setup-hooks/move-docs.sh
+      ../../build-support/setup-hooks/compress-man-pages.sh
       ../../build-support/setup-hooks/strip.sh
       ../../build-support/setup-hooks/patch-shebangs.sh
       gcc

pkgs/stdenv/generic/setup.sh

@@ -701,25 +701,6 @@ fixupPhase() {
 
     runHook preFixup
 
-    # Put man/doc/info under $out/share.
-    forceShare=${forceShare:=man doc info}
-    if [ -n "$forceShare" ]; then
-        for d in $forceShare; do
-            if [ -d "$prefix/$d" ]; then
-                if [ -d "$prefix/share/$d" ]; then
-                    echo "both $d/ and share/$d/ exists!"
-                else
-                    echo "fixing location of $d/ subdirectory"
-                    mkdir -p $prefix/share
-                    if [ -w $prefix/share ]; then
-                        mv -v $prefix/$d $prefix/share
-                        ln -sv share/$d $prefix
-                    fi
-                fi
-            fi
-        done;
-    fi
-
     # Apply fixup to each output.
     local output
     for output in $outputs; do