diff --git a/.github/workflows/root-ci-config/buildconfig/fedora44-clang_libcxx.txt b/.github/workflows/root-ci-config/buildconfig/fedora44-clang_libcxx.txt
new file mode 100644
index 0000000000000..439578254e761
--- /dev/null
+++ b/.github/workflows/root-ci-config/buildconfig/fedora44-clang_libcxx.txt
@@ -0,0 +1,38 @@
+# Build ROOT with Clang and libc++ instead of GNU libstdc++ on Linux.
+# The Fedora 44 image provides clang and libcxx/libcxxabi-devel packages.
+CMAKE_C_COMPILER=clang
+CMAKE_CXX_COMPILER=clang++
+CMAKE_GENERATOR=Ninja
+CMAKE_CXX_STANDARD=20
+soversion=ON
+libcxx=ON
+davix=OFF
+tpython=OFF
+minuit2_omp=OFF
+# All C++ dependencies must be built with the same toolchain: the ones
+# shipped by the distribution are compiled with libstdc++ and are ABI
+# incompatible with a libc++ ROOT build.
+builtin_civetweb=ON
+builtin_fftw3=ON
+builtin_freetype=ON
+builtin_ftgl=ON
+builtin_gif=ON
+builtin_gl2ps=ON
+builtin_gtest=ON
+builtin_gsl=ON
+builtin_jpeg=ON
+builtin_lz4=ON
+builtin_lzma=ON
+builtin_nlohmann=ON
+builtin_pcre=ON
+builtin_png=ON
+builtin_tbb=ON
+builtin_tiff=ON
+builtin_unuran=ON
+builtin_vdt=ON
+builtin_xrootd=ON
+builtin_xxhash=ON
+builtin_zlib=ON
+builtin_zstd=ON
+test_distrdf_dask=OFF
+test_distrdf_pyspark=OFF
diff --git a/.github/workflows/root-ci.yml b/.github/workflows/root-ci.yml
index 0af636192a117..ace11ab1be0c1 100644
--- a/.github/workflows/root-ci.yml
+++ b/.github/workflows/root-ci.yml
@@ -430,6 +430,11 @@ jobs:
             is_special: true
             property: "clang Ninja builtins auto-registration off"
             overrides: ["CMAKE_CXX_STANDARD=20"]
+          # Fedora 44 with Clang and libc++ instead of GNU libstdc++
+          - image: fedora44
+            platform_config: fedora44-clang_libcxx
+            is_special: true
+            property: "clang Ninja libc++"
           # Asan build
           - image: alma10
             platform_config: alma10-asan
diff --git a/interpreter/cling/lib/Interpreter/CMakeLists.txt b/interpreter/cling/lib/Interpreter/CMakeLists.txt
index 0474f07d9892a..8aab15bac107d 100644
--- a/interpreter/cling/lib/Interpreter/CMakeLists.txt
+++ b/interpreter/cling/lib/Interpreter/CMakeLists.txt
@@ -264,11 +264,19 @@ if (UNIX)
     endif()
   endif()
 
+  # If CMAKE_CXX_FLAGS selects the C++ standard library (e.g. -stdlib=libc++
+  # with a clang that defaults to libstdc++), cling has to look up the headers
+  # of that library, not the ones of the compiler default.
+  string(REGEX MATCH "-stdlib=[^ ]+" cling_cxx_stdlib "${CMAKE_CXX_FLAGS}")
+  if (cling_cxx_stdlib AND CLING_CXX_RLTV)
+    set(CLING_CXX_RLTV "${CLING_CXX_RLTV} ${cling_cxx_stdlib}")
+  endif()
+
   if(NOT CLING_CXX_HEADERS)
     if (CLING_CXX_PATH)
-      execute_process(COMMAND ${CLING_CXX_PATH} ${CLING_CXX_PATH_ARGS} -xc++ -E -v /dev/null
+      execute_process(COMMAND ${CLING_CXX_PATH} ${CLING_CXX_PATH_ARGS} ${cling_cxx_stdlib} -xc++ -E -v /dev/null
                       OUTPUT_QUIET ERROR_VARIABLE CLING_CXX_HEADERS)
-      set(CLING_CXX_PATH "${CLING_CXX_PATH} ${CLING_CXX_PATH_ARGS}")
+      set(CLING_CXX_PATH "${CLING_CXX_PATH} ${CLING_CXX_PATH_ARGS} ${cling_cxx_stdlib}")
     else()
       # convert CMAKE_CXX_FLAGS to a list for execute_process
       string(REPLACE "-fdiagnostics-color=always" "" cling_tmp_arg_list ${CMAKE_CXX_FLAGS})