Output path comparison

nix-env failed:
error:
       … while evaluating call site

       at «none»:0: (source not available)

       … while calling anonymous lambda

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/.gc-of-borg-outpaths.nix:48:12:

           47|   tweak = lib.mapAttrs
           48|     (name: val:
             |            ^
           49|       if name == "recurseForDerivations" then true

       … while evaluating call site

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/lib/attrsets.nix:1214:43:

         1213|     f:
         1214|     listToAttrs (map (n: nameValuePair n (f n)) names);
             |                                           ^
         1215|

       … while calling anonymous lambda

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/pkgs/top-level/release-lib.nix:145:6:

          144|   testOnCross = crossSystem: metaPatterns: f: forMatchingSystems metaPatterns
          145|     (system: hydraJob' (f (pkgsForCross crossSystem system)));
             |      ^
          146|

       … while evaluating call site

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/pkgs/top-level/release-lib.nix:145:14:

          144|   testOnCross = crossSystem: metaPatterns: f: forMatchingSystems metaPatterns
          145|     (system: hydraJob' (f (pkgsForCross crossSystem system)));
             |              ^
          146|

       … while calling 'hydraJob'

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/lib/customisation.nix:388:14:

          387|   */
          388|   hydraJob = drv:
             |              ^
          389|     let

       … while evaluating the attribute 'outPath'

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/lib/customisation.nix:404:13:

          403|           value = commonAttrs // {
          404|             outPath = output.outPath;
             |             ^
          405|             drvPath = output.drvPath;

       … while evaluating the attribute 'outPath'

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/lib/customisation.nix:352:13:

          351|             drvPath = assert condition; drv.${outputName}.drvPath;
          352|             outPath = assert condition; drv.${outputName}.outPath;
             |             ^
          353|           } //

       … while evaluating the attribute 'NIX_LDFLAGS' of the derivation 'attic-0.1.0'

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/pkgs/stdenv/generic/make-derivation.nix:331:7:

          330|     // (optionalAttrs (attrs ? name || (attrs ? pname && attrs ? version)) {
          331|       name =
             |       ^
          332|         let

       … while evaluating call site

       at «none»:0: (source not available)

       … while calling anonymous lambda

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/pkgs/stdenv/generic/make-derivation.nix:573:11:

          572|     mapAttrs
          573|       (n: v: assert assertMsg (isString v || isBool v || isInt v || isDerivation v)
             |           ^
          574|         "The ‘env’ attribute set can only contain derivation, string, boolean or integer attributes. The ‘${n}’ attribute is of type ${builtins.typeOf v}."; v)

       … while evaluating call site

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/pkgs/stdenv/generic/make-derivation.nix:573:21:

          572|     mapAttrs
          573|       (n: v: assert assertMsg (isString v || isBool v || isInt v || isDerivation v)
             |                     ^
          574|         "The ‘env’ attribute set can only contain derivation, string, boolean or integer attributes. The ‘${n}’ attribute is of type ${builtins.typeOf v}."; v)

       … while calling 'assertMsg'

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/lib/asserts.nix:41:5:

           40|     pred:
           41|     msg:
             |     ^
           42|     pred || builtins.throw msg;

       … while evaluating the attribute 'cc.libcxx.cxxabi.libName'

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/pkgs/build-support/cc-wrapper/default.nix:295:12:

          294|     inherit bintools;
          295|     inherit cc libc libcxx nativeTools nativeLibc nativePrefix isGNU isClang;
             |            ^
          296|

       error: attribute 'cxxabi' missing

       at /ofborg/checkout/1/repo/38dca4e3aa6bca43ea96d2fcc04e8229/mr-est/ofborg-evaluator-4/pkgs/by-name/at/attic-client/package.nix:47:24:

           46|   env = lib.optionalAttrs stdenv.cc.isClang {
           47|     NIX_LDFLAGS = "-l${stdenv.cc.libcxx.cxxabi.libName}";
             |                        ^
           48|   };