diff --git a/CMakeLists.txt b/CMakeLists.txt
index b5f070d0c7..ef5b3955e6 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -335,7 +335,7 @@ if (ENABLE_WFN91_LINALG_DISCOVERY_KIT)
   else(ENABLE_SCALAPACK)
     find_package(LAPACK REQUIRED)
     # Propagate LAPACK -> BLAS if not set
-    # (LAPACK necessacarily contains a BLAS linker by standard)
+    # (LAPACK necessarily contains a BLAS linker by standard)
     # TODO: Tell David to write a macro that hides this verbosity from user space
     if( NOT BLAS_LIBRARIES )
       set( BLAS_LIBRARIES "${LAPACK_LIBRARIES}" CACHE STRING "BLAS LIBRARIES" )
diff --git a/cmake/modules/FindOrFetchUmpire.cmake b/cmake/modules/FindOrFetchUmpire.cmake
index ac5896103d..6e77dcbb48 100644
--- a/cmake/modules/FindOrFetchUmpire.cmake
+++ b/cmake/modules/FindOrFetchUmpire.cmake
@@ -10,6 +10,13 @@ endif (NOT TARGET umpire)
 # if not found, build via FetchContent
 if (NOT TARGET umpire)
 
+  # caveat: on recent Ubuntu default libstdc++ provides filesystem, but if using older gcc (gcc-8) must link against
+  # libstdc++fs: https://bugs.launchpad.net/ubuntu/+source/gcc-8/+bug/1824721 ... skip the use of std::filesystem altogether with pre-9 gcc!!!
+  if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 9)
+    # disable by populating cache with compile test result variable
+    set(UMPIRE_ENABLE_FILESYSTEM OFF CACHE BOOL "Whether Umpire to use std::filesystem")
+  endif()
+
   include(FetchContent)
   FetchContent_Declare(
       umpire
diff --git a/external/umpire.cmake b/external/umpire.cmake
index 27c9ea21d2..3366a04f44 100644
--- a/external/umpire.cmake
+++ b/external/umpire.cmake
@@ -76,6 +76,15 @@ else()
         -DENABLE_LOGGING=OFF
         -DENABLE_ASSERTS=${enable_umpire_asserts}
         )
+
+    # caveat: on recent Ubuntu default libstdc++ provides filesystem, but if using older gcc (gcc-8) must link against
+    # libstdc++fs: https://bugs.launchpad.net/ubuntu/+source/gcc-8/+bug/1824721 ... skip the use of std::filesystem altogether with pre-9 gcc!!!
+    if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS 9)
+        # disable by populating cache with compile test result variable
+        list(APPEND UMPIRE_CMAKE_ARGS
+             -DUMPIRE_ENABLE_FILESYSTEM=OFF)
+    endif()
+
     if (ENABLE_CUDA)
         list(APPEND UMPIRE_CMAKE_ARGS
                 -DENABLE_CUDA=ON