1 files changed, 37 insertions, 0 deletions
diff --git a/nixpkgs/pkgs/build-support/setup-hooks/make-symlinks-relative.sh b/nixpkgs/pkgs/build-support/setup-hooks/make-symlinks-relative.sh
new file mode 100644
index 000000000000..b07b0c5ae804
--- /dev/null
+++ b/nixpkgs/pkgs/build-support/setup-hooks/make-symlinks-relative.sh
@@ -0,0 +1,37 @@
+# symlinks are often created in postFixup
+# don't use fixupOutputHooks, it is before postFixup
+postFixupHooks+=(_makeSymlinksRelativeInAllOutputs)
+
+# For every symlink in $output that refers to another file in $output
+# ensure that the symlink is relative. This removes references to the output
+# has from the resulting store paths and thus the NAR files.
+_makeSymlinksRelative() {
+    local symlinkTarget
+
+    if [ "${dontRewriteSymlinks-}" ] || [ ! -e "$prefix" ]; then
+       return
+    fi
+
+    while IFS= read -r -d $'\0' f; do
+        symlinkTarget=$(readlink "$f")
+        if [[ "$symlinkTarget"/ != "$prefix"/* ]]; then
+            # skip this symlink as it doesn't point to $prefix
+            continue
+        fi
+
+        if [ ! -e "$symlinkTarget" ]; then
+            echo "the symlink $f is broken, it points to $symlinkTarget (which is missing)"
+        fi
+
+        echo "rewriting symlink $f to be relative to $prefix"
+        ln -snrf "$symlinkTarget" "$f"
+
+    done < <(find $prefix -type l -print0)
+}
+
+_makeSymlinksRelativeInAllOutputs() {
+  local output
+  for output in $(getAllOutputNames); do
+    prefix="${!output}" _makeSymlinksRelative
+  done
+}