Use libdir suffix in versioned prefix as well

Use the lib/lib64 distinction for the versioned prefix, to avoid
a mismatch with the default prefix. This means that the versioned
prefix now has libraries in /usr/lib64/llvmN/lib64.

This should fix the issue https://src.fedoraproject.org/rpms/llvm/pull-request/446
ran into. This would also be needed if we wanted to switch to
installing into libexec.

Author: nikic

llvm.spec

@@ -210,12 +210,12 @@
 %global install_prefix %{_libdir}/llvm%{maj_ver}
 %global install_bindir %{install_prefix}/bin
 %global install_includedir %{install_prefix}/include
-%global install_libdir %{install_prefix}/lib
+%global install_libdir %{install_prefix}/%{_lib}
 %global install_datadir %{install_prefix}/share
 %global install_mandir %{install_prefix}/share/man
 %global install_libexecdir %{install_prefix}/libexec
-%global build_libdir llvm/%{_vpath_builddir}/lib
-%global unprefixed_libdir lib
+%global build_libdir llvm/%{_vpath_builddir}/%{_lib}
+%global unprefixed_libdir %{_lib}
 
 %if 0%{?rhel}
 %global targets_to_build "X86;AMDGPU;PowerPC;NVPTX;SystemZ;AArch64;BPF;WebAssembly"
@@ -316,7 +316,7 @@
 #region main package
 Name:		%{pkg_name_llvm}
 Version:	%{maj_ver}.%{min_ver}.%{patch_ver}%{?rc_ver:~rc%{rc_ver}}%{?llvm_snapshot_version_suffix:~%{llvm_snapshot_version_suffix}}
-Release:	8%{?dist}
+Release:	9%{?dist}
 Summary:	The Low Level Virtual Machine
 
 License:	Apache-2.0 WITH LLVM-exception OR NCSA
@@ -1507,6 +1507,10 @@ popd
 	%global cmake_config_args %{cmake_config_args} -DCMAKE_CXX_FLAGS_RELWITHDEBINFO="%{optflags} -DNDEBUG"
 %endif
 
+%if 0%{?__isa_bits} == 64
+	%global cmake_config_args %{cmake_config_args} -DLLVM_LIBDIR_SUFFIX=64
+%endif
+
 %if %{with gold}
 	%global cmake_config_args %{cmake_config_args} -DLLVM_BINUTILS_INCDIR=%{_includedir}
 %endif
@@ -1904,7 +1908,7 @@ install -p -m644 clang/bindings/python/clang/* %{buildroot}%{python3_sitelib}/cl
 %py_byte_compile %{__python3} %{buildroot}%{python3_sitelib}/clang
 
 # install scanbuild-py to python sitelib.
-mv %{buildroot}%{install_libdir}/{libear,libscanbuild} %{buildroot}%{python3_sitelib}
+mv %{buildroot}%{install_prefix}/lib/{libear,libscanbuild} %{buildroot}%{python3_sitelib}
 # Cannot use {libear,libscanbuild} style expansion in py_byte_compile.
 %py_byte_compile %{__python3} %{buildroot}%{python3_sitelib}/libear
 %py_byte_compile %{__python3} %{buildroot}%{python3_sitelib}/libscanbuild
@@ -1918,7 +1922,7 @@ done
 %else
 
 # Not sure where to put these python modules for the compat build.
-rm -Rf %{buildroot}%{install_libdir}/{libear,libscanbuild}
+rm -Rf %{buildroot}%{install_prefix}/lib/{libear,libscanbuild}
 rm %{buildroot}%{install_bindir}/scan-build-py
 
 # Not sure where to put the emacs integration files for the compat build.
@@ -3423,6 +3427,9 @@ fi
 
 #region changelog
 %changelog
+* Mon Jun 16 2025 Nikita Popov <[email protected]> - 20.1.6-9
+- Use libdir suffix in versioned prefix
+
 * Tue Jun 10 2025 Nikita Popov <[email protected]> - 20.1.6-8
 - Invert symlink direction
 - Fix i686 multilib installation (rhbz#2365079)