remove creation of relative links in package db (#569)

Changing from absolute links to relative links increases the length of
the parameters passed during linking by half. For things that have many
dependencies, this results in linking failing with an "argument list too
long" error.

Fixes #562

This change also updates the CI configuration files to help make
it easier for CI to cope with this sort of change.

Co-authored-by: Richard Wallace <richard.wallace@simspace.com>

Author: hamishmack

build.nix

@@ -16,16 +16,17 @@ let
 in rec {
   tests = import ./test/default.nix { inherit pkgs ifdLevel; };
 
-  tools = pkgs.recurseIntoAttrs
-    (pkgs.lib.mapAttrs (_: ghc:
-      let
-        tool = name: version: pkgs.buildPackages.haskell-nix.tool name { inherit version ghc; };
-      in pkgs.recurseIntoAttrs {
-          cabal-32 = tool "cabal" "3.2.0.0";
-          ghcide   = tool "ghcide" "object-code";
-        } // pkgs.lib.optionalAttrs (ghc.version == "8.6.5") {
-          cabal-30 = tool "cabal" "3.0.0.0";
-        }) { inherit (pkgs.buildPackages.haskell-nix.compiler) ghc865 ghc883; });
+  tools = pkgs.lib.optionalAttrs (ifdLevel >= 3)
+    (pkgs.recurseIntoAttrs
+      (pkgs.lib.mapAttrs (_: ghc:
+        let
+          tool = name: version: pkgs.buildPackages.haskell-nix.tool name { inherit version ghc; };
+        in pkgs.recurseIntoAttrs {
+            cabal-32 = tool "cabal" "3.2.0.0";
+            ghcide   = tool "ghcide" "object-code";
+          } // pkgs.lib.optionalAttrs (ghc.version == "8.6.5") {
+            cabal-30 = tool "cabal" "3.0.0.0";
+          }) { inherit (pkgs.buildPackages.haskell-nix.compiler) ghc865 ghc883; }));
 
   # Scripts for keeping Hackage and Stackage up to date, and CI tasks.
   # The dontRecurseIntoAttrs prevents these from building on hydra

builder/make-config-files.nix

@@ -179,9 +179,5 @@ in { identifier, component, fullName, flags ? {} }:
       sed -i -E "/^ ./{H;$!d} ; x ; s,^dynamic-library-dirs:.*,dynamic-library-dirs: $dynamicLinksDir," $f
     done
   '' + ''
-    # Use ''${pkgroot} relative paths so that we can relocate the package database
-    # along with referenced packages and still have it work on systems with
-    # or without nix installed.
-    sed -i 's|/nix/store/|''${pkgroot}/../../../|' $out/${packageCfgDir}/*.conf
     ${target-pkg} -v0 --package-db $out/${packageCfgDir} recache
   '')

ci.nix

@@ -37,31 +37,50 @@ dimension "Nixpkgs version" nixpkgsVersions (nixpkgsName: nixpkgs-pin:
     let pkgs = import pinnedNixpkgsSrc (nixpkgsArgs // { inherit system; });
         build = import ./build.nix { inherit pkgs ifdLevel; };
         platformFilter = platformFilterGeneric pkgs system;
+        compilers = {
+          inherit (pkgs.haskell-nix.compiler) ghc865 ghc883;
+        };
     in filterAttrsOnlyRecursive (_: v: platformFilter v) {
       # Native builds
       # TODO: can we merge this into the general case by picking an appropriate "cross system" to mean native?
-      native = pkgs.recurseIntoAttrs {
+      native = pkgs.recurseIntoAttrs ({
         inherit (build) tests tools maintainer-scripts maintainer-script-cache;
+        ghc = pkgs.recurseIntoAttrs compilers;
+      } // pkgs.lib.optionalAttrs (ifdLevel >= 1) {
+        iserv-proxy = pkgs.recurseIntoAttrs (
+          pkgs.lib.mapAttrs (ghcName: _:
+            pkgs.ghc-extra-packages."${ghcName}".iserv-proxy.components.exes.iserv-proxy
+          ) compilers);
+      } // pkgs.lib.optionalAttrs (ifdLevel >= 2) {
         hello = (pkgs.haskell-nix.hackage-package { name = "hello"; version = "1.0.0.2"; }).components.exes.hello;
-        iserv-proxy = pkgs.ghc-extra-packages.ghc865.iserv-proxy.components.exes.iserv-proxy;
-        ghc = pkgs.recurseIntoAttrs pkgs.haskell-nix.compiler;
-      };
+      });
     }
     //
     dimension "Cross system" (crossSystems nixpkgsName genericPkgs system) (crossSystemName: crossSystem:
       # Cross builds
       let pkgs = import pinnedNixpkgsSrc (nixpkgsArgs // { inherit system crossSystem; });
           build = import ./build.nix { inherit pkgs ifdLevel; };
-      in pkgs.recurseIntoAttrs {
+      in pkgs.recurseIntoAttrs (pkgs.lib.optionalAttrs (ifdLevel >= 1) {
+        ghc = pkgs.recurseIntoAttrs compilers;
         # TODO: look into making tools work when cross compiling
         # inherit (build) tools;
+      } // pkgs.lib.optionalAttrs (ifdLevel >= 2) {
+        remote-iserv = pkgs.recurseIntoAttrs (
+          pkgs.lib.mapAttrs (ghcName: _:
+            pkgs.ghc-extra-packages."${ghcName}".remote-iserv.components.exes.remote-iserv
+          ) compilers);
+        iserv-proxy = pkgs.recurseIntoAttrs (
+          pkgs.lib.mapAttrs (ghcName: _:
+            pkgs.ghc-extra-packages."${ghcName}".iserv-proxy.components.exes.iserv-proxy
+          ) compilers);
+      } // pkgs.lib.optionalAttrs (ifdLevel >= 3) {
         hello = (pkgs.haskell-nix.hackage-package { name = "hello"; version = "1.0.0.2"; }).components.exes.hello;
-        iserv-proxy = pkgs.ghc-extra-packages.ghc865.iserv-proxy.components.exes.iserv-proxy;
-        remote-iserv = pkgs.ghc-extra-packages.ghc865.remote-iserv.components.exes.remote-iserv;
       }
       //
       # Tests are broken on aarch64 cross https://github.com/input-output-hk/haskell.nix/issues/513
-      pkgs.lib.optionalAttrs (crossSystemName != "aarch64-multiplatform") { inherit (build) tests; }
+      pkgs.lib.optionalAttrs (crossSystemName != "aarch64-multiplatform") {
+        inherit (build) tests;
+      })
     )
   )
 )

overlays/haskell.nix

@@ -501,7 +501,6 @@ self: super: {
             happy = self.buildPackages.haskell-nix.bootstrap.packages.happy;
             hscolour = self.buildPackages.haskell-nix.bootstrap.packages.hscolour;
             ghc865 = self.buildPackages.haskell-nix.compiler.ghc865;
-            ghc882 = self.buildPackages.haskell-nix.compiler.ghc882;
             ghc883 = self.buildPackages.haskell-nix.compiler.ghc883;
             ghc-boot-packages-nix = self.recurseIntoAttrs
               (builtins.mapAttrs (_: self.recurseIntoAttrs)