diff --git a/llvm.spec b/llvm.spec
index 3ff1552..3498a35 100644
--- a/llvm.spec
+++ b/llvm.spec
@@ -1,3 +1,6 @@
+# We are building with clang for faster/lower memory LTO builds.
+%global toolchain clang
+
 # Components enabled if supported by target architecture:
 %define gold_arches %{ix86} x86_64 %{arm} aarch64 %{power64} s390x
 %ifarch %{gold_arches}
@@ -64,7 +67,7 @@
 
 Name:		%{pkg_name}
 Version:	%{maj_ver}.%{min_ver}.%{patch_ver}%{?rc_ver:~rc%{rc_ver}}
-Release:	4%{?dist}
+Release:	5%{?dist}
 Summary:	The Low Level Virtual Machine
 
 License:	NCSA
@@ -85,6 +88,7 @@ Patch2:		0001-XFAIL-missing-abstract-variable.ll-test-on-ppc64le.patch
 
 BuildRequires:	gcc
 BuildRequires:	gcc-c++
+BuildRequires:	clang
 BuildRequires:	cmake
 BuildRequires:	ninja-build
 BuildRequires:	zlib-devel
@@ -545,6 +549,9 @@ fi
 %endif
 
 %changelog
+* Mon Oct 18 2021 Tom Stellard <tstellar@redhat.com> - 13.0.0-5
+- Build with clang
+
 * Fri Oct 08 2021 Tom Stellard <tstellar@redhat.com> - 13.0.0-4
 - Fix default triple on arm