diff --git a/library/compiler-builtins/.github/workflows/main.yml b/library/compiler-builtins/.github/workflows/main.yml
index 01188636621f..6518a4dd6880 100644
--- a/library/compiler-builtins/.github/workflows/main.yml
+++ b/library/compiler-builtins/.github/workflows/main.yml
@@ -87,6 +87,7 @@ jobs:
         - target: x86_64-pc-windows-msvc
           os: windows-latest
           rust: nightly
+          test_unc: 1
         - target: i686-pc-windows-gnu
           os: windows-latest
           rust: nightly-i686-gnu
diff --git a/library/compiler-builtins/ci/run.sh b/library/compiler-builtins/ci/run.sh
index f05744e87200..b2728eacf352 100755
--- a/library/compiler-builtins/ci/run.sh
+++ b/library/compiler-builtins/ci/run.sh
@@ -33,7 +33,7 @@ else
 fi
 
 if [ "${TEST_UNC:-}" = "1" ]; then
-    run="cargo build --manifest-path testcrate/Cargo.toml --target $target --target-dir \"\\\\?\\$(pwd)\""
+    run="cargo build --manifest-path testcrate/Cargo.toml --target $target --target-dir \\\\?\\$TEMP\\test_unc"
     $run
     $run --release
     $run --features c