diff --git a/llvm.spec b/llvm.spec
index 07885985e98..e560ec6cdad 100644
--- a/llvm.spec
+++ b/llvm.spec
@@ -3,7 +3,7 @@
 ## INITENV +PATH PYTHON3PATH %{i}/lib64/python%{cms_python3_major_minor_version}/site-packages
 
 BuildRequires: cmake ninja
-Requires: gcc zlib python3 libxml2 zstd
+Requires: gcc zlib python3 libxml2 zstd libunwind
 %{!?without_cuda:Requires: cuda}
 
 %define llvmCommit 02c7568fc9f555b2c72fc169c8c68e2116d97382
@@ -35,13 +35,14 @@ rm -rf %{_builddir}/build
 mkdir -p %{_builddir}/build
 cd %{_builddir}/build
 
+host_triple=$(gcc -dumpmachine)
 cmake %{_builddir}/llvm-%{realversion}-%{llvmCommit}/llvm \
   -G Ninja \
 %if 0%{!?use_system_gcc:1}
-  -DGCC_INSTALL_PREFIX="${GCC_ROOT}" \
   -DLLVM_BINUTILS_INCDIR:STRING="${GCC_ROOT}/include" \
 %endif
   -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;compiler-rt;lld;openmp" \
+  -DLLVM_ENABLE_RUNTIMES="libcxx;libcxxabi;libunwind" \
   -DCMAKE_INSTALL_PREFIX:PATH="%{i}" \
   -DCMAKE_BUILD_TYPE:STRING=Release \
   -DLLVM_LIBDIR_SUFFIX:STRING=64 \
@@ -50,14 +51,14 @@ cmake %{_builddir}/llvm-%{realversion}-%{llvmCommit}/llvm \
   -DLLVM_ENABLE_EH:BOOL=ON \
   -DLLVM_ENABLE_PIC:BOOL=ON \
   -DLLVM_ENABLE_RTTI:BOOL=ON \
-  -DLLVM_HOST_TRIPLE=$(gcc -dumpmachine) \
+  -DLLVM_HOST_TRIPLE=${host_triple} \
   -DLLVM_TARGETS_TO_BUILD:STRING="X86;PowerPC;AArch64;RISCV;NVPTX" \
 %if 0%{!?without_cuda:1}
   -DLIBOMPTARGET_NVPTX_ALTERNATE_HOST_COMPILER=/usr/bin/gcc \
   -DLIBOMPTARGET_NVPTX_COMPUTE_CAPABILITIES="%omptarget_cuda_archs" \
 %endif
   -DCMAKE_REQUIRED_INCLUDES="${ZLIB_ROOT}/include" \
-  -DCMAKE_PREFIX_PATH="${ZLIB_ROOT};${LIBXML2_ROOT};${ZSTD_ROOT}"
+  -DCMAKE_PREFIX_PATH="${ZLIB_ROOT};${LIBXML2_ROOT};${ZSTD_ROOT};${LIBUNWIND_ROOT}"
 
 ninja -v %{makeprocesses}
 ninja -v %{makeprocesses} check-clang-tools
@@ -67,6 +68,9 @@ bin/clang-tidy --checks=* --list-checks | grep cms-handle
 cd ../build
 ninja -v %{makeprocesses} install
 
+#Create libomp symlink
+host_triple=$(gcc -dumpmachine)
+
 BINDINGS_PATH=%{i}/lib64/python%{cms_python3_major_minor_version}/site-packages
 PKG_INFO_FILE=$BINDINGS_PATH/clang-%{realversion}-py%{cms_python3_major_minor_version}.egg-info/PKG-INFO
 mkdir -p $BINDINGS_PATH
@@ -85,7 +89,20 @@ rm -f %{i}/bin/FileRadar.scpt %{i}/bin/GetRadarVersion.scpt
 # Avoid dependency on /usr/bin/python, Darwin + Xcode specific
 rm -f %{i}/bin/set-xcode-analyzer
 
+%if 0%{!?use_system_gcc:1}
+pushd %{i}/bin
+  [ -e clang++.cfg ] && exit 1
+  [ -e clang.cfg   ] && exit 1
+  echo "--gcc-toolchain=$GCC_ROOT" > clang++.cfg
+  echo "--target=$host_triple"    >> clang++.cfg
+  ln -s clang++.cfg clang.cfg
+popd
+%endif
+
 %post
 %{relocateConfig}include/llvm/Config/llvm-config.h
 %{relocateConfig}include/clang/Config/config.h
 %{relocateConfig}lib64/cmake/llvm/LLVMConfig.cmake
+%if 0%{!?use_system_gcc:1}
+%{relocateConfig}bin/clang++.cfg
+%endif
diff --git a/scram-tools.file/tools/llvm/llvm-ccompiler.xml b/scram-tools.file/tools/llvm/llvm-ccompiler.xml
index 7b11219668c..ec9dcee397e 100644
--- a/scram-tools.file/tools/llvm/llvm-ccompiler.xml
+++ b/scram-tools.file/tools/llvm/llvm-ccompiler.xml
@@ -1,10 +1,7 @@
-  <tool name="llvm-ccompiler" version="@TOOL_VERSION@" type="compiler" revision="1">
+  <tool name="llvm-ccompiler" version="@TOOL_VERSION@" type="compiler" revision="2">
     <use name="gcc-ccompiler"/>
     <client>
       <environment name="LLVM_CCOMPILER_BASE" default="@TOOL_ROOT@"/>
       <environment name="CC" value="$LLVM_CCOMPILER_BASE/bin/clang"/>
     </client>
-%if 0%{!?use_system_gcc:1}
-    <flags CFLAGS="--gcc-toolchain=@GCC_ROOT@"/>
-%endif
   </tool>
diff --git a/scram-tools.file/tools/llvm/llvm-cxxcompiler.xml b/scram-tools.file/tools/llvm/llvm-cxxcompiler.xml
index 3ad30233f57..5fb434b0dc8 100644
--- a/scram-tools.file/tools/llvm/llvm-cxxcompiler.xml
+++ b/scram-tools.file/tools/llvm/llvm-cxxcompiler.xml
@@ -1,4 +1,4 @@
-  <tool name="llvm-cxxcompiler" version="@TOOL_VERSION@" type="compiler" revision="1">
+  <tool name="llvm-cxxcompiler" version="@TOOL_VERSION@" type="compiler" revision="2">
     <use name="gcc-cxxcompiler"/>
     <client>
       <environment name="LLVM_CXXCOMPILER_BASE" default="@TOOL_ROOT@"/>
@@ -33,9 +33,6 @@
     <flags CXXFLAGS="-Wno-tautological-type-limit-compare"/>
     <flags CXXFLAGS="-Wno-vla-cxx-extension"/>
     <flags CXXFLAGS="-fsized-deallocation"/>
-%if 0%{!?use_system_gcc:1}
-    <flags CXXFLAGS="--gcc-toolchain=@GCC_ROOT@"/>
-%endif
     <runtime name="@OS_RUNTIME_LDPATH_NAME@" value="$LLVM_CXXCOMPILER_BASE/lib64" type="path"/>
     <runtime name="PATH" value="$LLVM_CXXCOMPILER_BASE/bin" type="path"/>
   </tool>