diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 8e7875d..2e1d39d 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -478,6 +478,7 @@ jobs:
     defaults:
       run:
         shell: powershell
+    timeout-minutes: 30
     name: vcpkg - windows
     steps:
     - name: git clone
@@ -507,10 +508,16 @@ jobs:
         cd build/vcpkg/test
         cmake .
         cmake --build . --parallel
+
+    # the tests complete in well under a second; the 2-minute timeout is a
+    # safety net so that a hung test process fails the job quickly instead of
+    # freezing the runner for an hour (see the 2026-11-03 freeze, caused by
+    # undefined behaviour in the tree_reading test under MSVC debug CRT)
     - name: test vcpkg port - test
+      timeout-minutes: 2
       run: |
         cd build/vcpkg/test
-        cmake --build . --config Debug --target run-library-tests
+        cmake --build . --target run-library-tests
     - name: upload vcpkg logs to artifacts
       if: always() # even if previous steps fail, this one needs to be run
       uses: actions/upload-artifact@v4
diff --git a/tests/unit/src/tree_reading.cpp b/tests/unit/src/tree_reading.cpp
index 9cc3ac2..fb84a86 100644
--- a/tests/unit/src/tree_reading.cpp
+++ b/tests/unit/src/tree_reading.cpp
@@ -1,6 +1,7 @@
 #include <fsif/native_file.hpp>
 #include <tst/check.hpp>
 #include <tst/set.hpp>
+#include <utki/debug.hpp>
 
 #include "../../../src/tml/tree.hpp"
 
@@ -70,7 +71,15 @@ const tst::set set("tree_reading", [](tst::suite& suite) {
 		tst::check(i != roots.end(), SL);
 		tst::check(i->value == "", SL);
 		tst::check(i->value.length() == 0, SL);
-		tst::check(i->children.size() == 0, SL) << i->children.front().value.string;
+		tst::check(
+			i->children.size() == 0,
+			[&i](auto& o) {
+				// if the check has failed, then the children list is not empty
+				utki::assert(!i->children.empty(), SL);
+				o << i->children.front().value.string;
+			},
+			SL
+		);
 
 		++i;
 		tst::check(i != roots.end(), SL);