treewide: Use pkgs/build-support/roles.bash to remove copy pasta

Also fix some setup hooks that unnecessarily used environment hooks,
which revolted in the same variable being modified too many times.

2 files changed, 7 insertions, 16 deletions

diff --git a/pkgs/development/libraries/libiconv/default.nix b/pkgs/development/libraries/libiconv/default.nix
index a4e6fed88e1..169a4d38bb5 100644
--- a/pkgs/development/libraries/libiconv/default.nix
+++ b/pkgs/development/libraries/libiconv/default.nix
@@ -14,7 +14,10 @@ stdenv.mkDerivation rec {
     sha256 = "0y1ij745r4p48mxq84rax40p10ln7fc7m243p8k8sia519i3dxfc";
   };
 
-  setupHook = ./setup-hook.sh;
+  setupHooks = [
+    ../../../build-support/setup-hooks/role.bash
+    ./setup-hook.sh
+  ];
 
   postPatch =
     lib.optionalString ((hostPlatform != buildPlatform && hostPlatform.libc == "msvcrt") || stdenv.cc.nativeLibc)
diff --git a/pkgs/development/libraries/libiconv/setup-hook.sh b/pkgs/development/libraries/libiconv/setup-hook.sh
index 78222dddbf1..d20e94513e2 100644
--- a/pkgs/development/libraries/libiconv/setup-hook.sh
+++ b/pkgs/development/libraries/libiconv/setup-hook.sh
@@ -1,18 +1,6 @@
 # libiconv must be listed in load flags on non-Glibc
 # it doesn't hurt to have it in Glibc either though
-iconvLdflags() {
-    # The `depHostOffset` describes how the host platform of the dependencies
-    # are slid relative to the depending package. It is brought into scope of
-    # the environment hook defined as the role of the dependency being applied.
-    case $depHostOffset in
-        -1) local role='BUILD_' ;;
-        0)  local role='' ;;
-        1)  local role='TARGET_' ;;
-        *)  echo "cc-wrapper: Error: Cannot be used with $depHostOffset-offset deps" >2;
-            return 1 ;;
-    esac
 
-    export NIX_${role}LDFLAGS+=" -liconv"
-}
-
-addEnvHooks "$hostOffset" iconvLdflags
+# See pkgs/build-support/setup-hooks/role.bash
+getHostRole
+export NIX_${role_pre}LDFLAGS+=" -liconv"