rustc: Fix configure flags for custom target JSON

For custom target JSON, rustc bootstrap expects config to be set for
target."/path/to/target.json", so use that.

Changed files
+3 -3
pkgs
development
compilers
rust
+3 -3
pkgs/development/compilers/rust/rustc.nix
···
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;