diff --git a/.github/workflows/test-coverage.yml b/.github/workflows/test-coverage.yml
index 9edfe7cc96852..9f3c6dd646e7c 100644
--- a/.github/workflows/test-coverage.yml
+++ b/.github/workflows/test-coverage.yml
@@ -61,13 +61,15 @@ jobs:
       options: '--security-opt label=disable --rm'
       env:
         OS_APPLICATION_CREDENTIAL_ID: '7f5b64a265244623a3a933308569bdba'
+        # Handle up to 256 profiles being generated concurrently and merged
+        LLVM_PROFILE_FILE: 'llvm_profile_out_%256m.profraw'
         PYTHONUNBUFFERED: true
 
     steps:
-      - name: Install cov packages
+      - name: Install clang and coverage packages
         run: |
           sudo dnf -y update
-          sudo dnf -y install lcov
+          sudo dnf -y install clang llvm
           pip3 install gcovr
 
       - name: Checkout
@@ -86,7 +88,11 @@ jobs:
 
       - name: Apply option override from matrix for this job
         env:
-          OVERRIDE: "coverage=On"
+          OVERRIDE: |
+            coverage=On
+            CMAKE_CXX_COMPILER=clang++
+            CMAKE_C_COMPILER=clang
+            CMAKE_BUILD_TYPE=Release
           FILE: .github/workflows/root-ci-config/buildconfig/fedora38.txt
         shell: bash
         run: |
@@ -133,13 +139,17 @@ jobs:
                     --repository     ${{ github.server_url }}/${{ github.repository }}
               "
 
+      - name: Merge raw coverage reports
+        run: |
+          find . -name '*.profraw' > input-profraw.txt
+          llvm-profdata merge -sparse --input-files=input-profraw.txt --output=merged.profdata
+          llvm-cov export -format=lcov -instr-profile merged.profdata
+          ls -ltr
       - name: Upload coverage to Codecov
         if: ${{ !cancelled() }}
         uses: codecov/codecov-action@v3
         with:
           env_vars: OS,PYTHON
           fail_ci_if_error: true
-          files: /github/home/ROOT-CI/build/cobertura-cov.xml
-          flags: unittests
-          name: codecov-umbrella
+          files: /github/home/ROOT-CI/build/merged.profdata.lcov
           verbose: true
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7be06c7ca3a06..40390fd69a7c0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -311,12 +311,20 @@ endif()
 
 #---Enable test coverage -----------------------------------------------------------------------
 if(coverage)
-  set(GCC_COVERAGE_COMPILE_FLAGS "-fprofile-arcs -ftest-coverage")
-  set(GCC_COVERAGE_LINK_FLAGS    "-fprofile-arcs")
-  set(CMAKE_CXX_FLAGS            "${CMAKE_CXX_FLAGS} ${GCC_COVERAGE_COMPILE_FLAGS}")
-  set(CMAKE_EXE_LINKER_FLAGS     "${CMAKE_EXE_LINKER_FLAGS} ${GCC_COVERAGE_LINK_FLAGS}")
-  set(CMAKE_SHARED_LINKER_FLAGS  "${CMAKE_SHAREDLINKER_FLAGS} ${GCC_COVERAGE_LINK_FLAGS}")
-  set(CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS} ${GCC_COVERAGE_COMPILE_FLAGS}")
+  if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+    # GCC
+    set(COVERAGE_COMPILE_FLAGS "-fprofile-arcs -ftest-coverage")
+    set(COVERAGE_LINK_FLAGS    "-fprofile-arcs")
+  elseif (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+    set(COVERAGE_COMPILE_FLAGS "-fprofile-instr-generate -fcoverage-mapping")
+    set(COVERAGE_LINK_FLAGS    "-fprofile-instr-generate")
+  else()
+    message(FATAL_ERROR "Coverage currently only supported for GCC and clang!")
+  endif()
+  set(CMAKE_CXX_FLAGS            "${CMAKE_CXX_FLAGS} ${COVERAGE_COMPILE_FLAGS}")
+  set(CMAKE_EXE_LINKER_FLAGS     "${CMAKE_EXE_LINKER_FLAGS} ${COVERAGE_LINK_FLAGS}")
+  set(CMAKE_SHARED_LINKER_FLAGS  "${CMAKE_SHAREDLINKER_FLAGS} ${COVERAGE_LINK_FLAGS}")
+  set(CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS "${CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS} ${COVERAGE_COMPILE_FLAGS}")
 endif()
 
 #--- Enable build timing -----------------------------------------------------------------------