diff --git a/libomp.spec b/libomp.spec
index 8986aa9..95ee74f 100644
--- a/libomp.spec
+++ b/libomp.spec
@@ -5,21 +5,23 @@
 %{llvm_sb}
 %endif
 
-%global toolchain gcc
-
-%global maj_ver 17
-%global libomp_version %{maj_ver}.0.6
+%global maj_ver 18
+%global min_ver 1
+%global libomp_version %{maj_ver}.%{min_ver}.6
 #global rc_ver 4
 %global libomp_srcdir openmp-%{libomp_version}%{?rc_ver:rc%{rc_ver}}.src
-%global so_suffix %{maj_ver}
+%global so_suffix %{maj_ver}.%{min_ver}
 
 %if %{with snapshot_build}
 %undefine rc_ver
 %global maj_ver %{llvm_snapshot_version_major}
 %global libomp_version %{llvm_snapshot_version}
-%global so_suffix %{maj_ver}%{llvm_snapshot_version_suffix}
+%global so_suffix %{maj_ver}.%{min_ver}%{llvm_snapshot_version_suffix}
 %endif
 
+%global libomp_srcdir openmp-%{libomp_version}%{?rc_ver:rc%{rc_ver}}.src
+
+%global toolchain clang
 
 # Opt out of https://fedoraproject.org/wiki/Changes/fno-omit-frame-pointer
 # https://bugzilla.redhat.com/show_bug.cgi?id=2158587
@@ -67,10 +69,7 @@ BuildRequires: llvm-cmake-utils
 
 Requires: elfutils-libelf%{?isa}
 
-Obsoletes: libomp-test < 17.0.2
-
-# libomp does not support s390x.
-ExcludeArch: s390x
+Obsoletes: libomp-test < 18.1.6
 
 %description
 OpenMP runtime for clang.
@@ -90,11 +89,6 @@ OpenMP header files.
 %autosetup -n %{libomp_srcdir} -p2
 
 %build
-
-%if "%toolchain" == "gcc"
-# Building openmp with LTO fails with GCC but works with Clang
-%define _lto_cflags %{nil}
-%endif
 %cmake	-GNinja \
 	-DLIBOMP_INSTALL_ALIASES=OFF \
 	-DCMAKE_MODULE_PATH=%{_datadir}/llvm/cmake/Modules \
@@ -131,25 +125,32 @@ rm -rf %{buildroot}%{_libdir}/libarcher_static.a
 %endif
 %ifnarch %{ix86} %{arm}
 # libomptarget is not supported on 32-bit systems.
+# s390x does not support the offloading plugins.
+%ifnarch s390x
 %{_libdir}/libomptarget.rtl.amdgpu.so.%{so_suffix}
 %{_libdir}/libomptarget.rtl.cuda.so.%{so_suffix}
 %{_libdir}/libomptarget.rtl.%{libomp_arch}.so.%{so_suffix}
+%endif
 %{_libdir}/libomptarget.so.%{so_suffix}
 %endif
 
 %files devel
 %{_prefix}/lib/clang/%{maj_ver}/include/omp.h
+%{_prefix}/lib/clang/%{maj_ver}/include/ompx.h
 %ifnarch %{arm}
 %{_prefix}/lib/clang/%{maj_ver}/include/omp-tools.h
 %{_prefix}/lib/clang/%{maj_ver}/include/ompt.h
 %{_prefix}/lib/clang/%{maj_ver}/include/ompt-multiplex.h
 %endif
-%{_libdir}/cmake/openmp/FindOpenMPTarget.cmake
+%{_libdir}/cmake/openmp/
 %ifnarch %{ix86} %{arm}
 # libomptarget is not supported on 32-bit systems.
+# s390x does not support the offloading plugins.
+%ifnarch s390x
 %{_libdir}/libomptarget.rtl.amdgpu.so
 %{_libdir}/libomptarget.rtl.cuda.so
 %{_libdir}/libomptarget.rtl.%{libomp_arch}.so
+%endif
 %{_libdir}/libomptarget.devicertl.a
 %{_libdir}/libomptarget-amdgpu-*.bc
 %{_libdir}/libomptarget-nvptx-*.bc
@@ -157,7 +158,8 @@ rm -rf %{buildroot}%{_libdir}/libarcher_static.a
 %endif
 
 %changelog
-%{?llvm_snapshot_changelog_entry}
+* Mon Jun 03 2024 Konrad Kleine <kkleine@redhat.com> - 18.1.6-1
+- Update to 18.1.6
 
 * Mon Dec 11 2023 Timm Bäder <tbaeder@redhat.com> - 17.0.6-1
 - Update to 17.0.6
diff --git a/sources b/sources
index a4e0de6..ea85e92 100644
--- a/sources
+++ b/sources
@@ -1,2 +1,2 @@
-SHA512 (openmp-17.0.6.src.tar.xz.sig) = 58fb951620d3494e016f0eeefb1cd28d86eb9ecc7894163ed96e8818573f6ed6b6f58d63884799fd052c943e5a63dec39193039f8499b99a55bfd8316c24a55f
-SHA512 (openmp-17.0.6.src.tar.xz) = 836c48db873e3da64835913c2c1d80efaebdfc7061f153acc7b478ea0d73b9c546a09d70dd1465e3e92684947c4a9cb197886b29cbd42418a778faa56b08cc5e
+SHA512 (openmp-18.1.6.src.tar.xz) = f96f5fd4c508f1390e53b943237aa7e1db1301ef660f0864305556d581275576d585ef222a82d2359d43ad8ed166096d9ec6c05ab0ee57a01679cff6b4ecba4b
+SHA512 (openmp-18.1.6.src.tar.xz.sig) = c7e2652ebdde9ab60d56e8767ceeb4536ca0daa405d1c0d4d1e0755aecd8ec96c51824af380faa535afcab0c46fac3395e2a9e55f26f3de87548c95b11ac72b6
diff --git a/tests/README.md b/tests/README.md
new file mode 100644
index 0000000..39c94b2
--- /dev/null
+++ b/tests/README.md
@@ -0,0 +1,6 @@
+# Gating testplans for libomp
+
+The tests for libomp are in a separate repo: https://src.fedoraproject.org/tests/libomp
+This directory should contain only fmf plans (such as build-gating.fmf) which import
+the tests from the tests repo. This can be done using the "url" parameter of the
+plan's "discover" step. Reference: https://tmt.readthedocs.io/en/stable/spec/plans.html#fmf