* Add the Nix corepkgs to the end of the search path. This makes it

possible for other Nix expressions to use corepkgs (mostly useful
  for the buildenv function).

src/libexpr/eval.cc

@@ -186,6 +186,8 @@ EvalState::EvalState()
     searchPathInsertionPoint = searchPath.end();
     Strings paths = tokenizeString(getEnv("NIX_PATH", ""), ":");
     foreach (Strings::iterator, i, paths) addToSearchPath(*i);
+    printMsg(lvlError, nixDataDir);
+    addToSearchPath("nix=" + nixDataDir + "/nix/corepkgs");
     searchPathInsertionPoint = searchPath.begin();
 }
 

tests/lang/eval-okay-search-path.nix

@@ -1,3 +1,3 @@
+assert builtins.pathExists <nix/buildenv>;
+
 import <a.nix> + import <b.nix> + import <c.nix> + import <dir5/c.nix>
-
-

tests/lang/eval-okay-search-path.out

@@ -1 +1 @@
-"abc"
+"abcc"