diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7945ee63a3078..9531e47d9977f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -469,6 +469,13 @@ if(MSVC)
 endif()
 
 if(runtime_cxxmodules)
+  if(NOT ROOT_CONFIGURED_FROM_CACHE)
+    # When using cmake --fresh (or changing the toolchain), remove possibly stale pcms that are not tracked by CMake
+    set(ROOT_CONFIGURED_FROM_CACHE True CACHE BOOL "Shows if ROOT is configured from an existing CMake cache")
+    mark_as_advanced(ROOT_CONFIGURED_FROM_CACHE)
+    file(GLOB left_over_pcms ${CMAKE_BINARY_DIR}/lib/*.pcm)
+    file(REMOVE ${left_over_pcms})
+  endif()
   # Dummy target that does nothing, we don't need a PCH for modules.
   # Onepcm target has all dependencies needed for allDict.cxx.pch, which allow
   # to test hsimple.C after all C++ modules are updated.