diff --git a/pkgs/development/compilers/rust/rustc.nix b/pkgs/development/compilers/rust/rustc.nix
index a9f3b78a11b5..84ab93741182 100644
--- a/pkgs/development/compilers/rust/rustc.nix
+++ b/pkgs/development/compilers/rust/rustc.nix
@@ -111,9 +111,9 @@ stdenv.mkDerivation (finalAttrs: {
         stdenv: "${prefixForStdenv stdenv}${if (stdenv.cc.isClang or false) then "clang" else "cc"}";
       cxxPrefixForStdenv =
         stdenv: "${prefixForStdenv stdenv}${if (stdenv.cc.isClang or false) then "clang++" else "c++"}";
-      setBuild = "--set=target.\"${stdenv.buildPlatform.rust.rustcTarget}\"";
-      setHost = "--set=target.\"${stdenv.hostPlatform.rust.rustcTarget}\"";
-      setTarget = "--set=target.\"${stdenv.targetPlatform.rust.rustcTarget}\"";
+      setBuild = "--set=target.\"${stdenv.buildPlatform.rust.rustcTargetSpec}\"";
+      setHost = "--set=target.\"${stdenv.hostPlatform.rust.rustcTargetSpec}\"";
+      setTarget = "--set=target.\"${stdenv.targetPlatform.rust.rustcTargetSpec}\"";
       ccForBuild = ccPrefixForStdenv pkgsBuildBuild.targetPackages.stdenv;
       cxxForBuild = cxxPrefixForStdenv pkgsBuildBuild.targetPackages.stdenv;
       ccForHost = ccPrefixForStdenv pkgsBuildHost.targetPackages.stdenv;