!3 Add libcxx-12.0.1 source code and build script

From: @lukewzh 
Reviewed-by: @cf-zhao 
Signed-off-by: @cf-zhao

0001-PATCH-libcxx-Remove-monorepo-requirement.patch

@@ -0,0 +1,35 @@
+From fc46c464795f965c4cdbc321058f24191af8e40c Mon Sep 17 00:00:00 2001
+From: Tom Stellard <tstellar@redhat.com>
+Date: Tue, 11 Aug 2020 07:55:18 -0700
+Subject: [PATCH] [PATCH][libcxx] Remove monorepo requirement
+ 
+---
+ libcxx/CMakeLists.txt | 9 ---------
+ 1 file changed, 9 deletions(-)
+ 
+diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
+index 9bf1a02..5348a15 100644
+--- a/libcxx/CMakeLists.txt
++++ b/libcxx/CMakeLists.txt
+@@ -1,10 +1,3 @@
+-# See https://libcxx.llvm.org/docs/BuildingLibcxx.html for instructions on how
+-# to build libcxx with CMake.
+-
+-if (NOT IS_DIRECTORY "${CMAKE_CURRENT_LIST_DIR}/../libcxxabi")
+-  message(FATAL_ERROR "libc++ now requires being built in a monorepo layout with libcxxabi available")
+-endif()
+-
+ #===============================================================================
+ # Setup Project
+ #===============================================================================
+@@ -39,8 +32,6 @@ if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR OR LIBCXX_STANDALONE_BUIL
+   set(LIBCXX_STANDALONE_BUILD 1)
+   set(LLVM_LIT_OUTPUT_DIR "${LIBCXX_BINARY_DIR}/bin")
+ 
+-  # Find the LLVM sources and simulate LLVM CMake options.
+-  include(HandleOutOfTreeLLVM)
+ endif()
+ 
+ if (LIBCXX_STANDALONE_BUILD)
+-- 
+1.8.3.1

0001-libcxx-Remove-monorepo-requirement.patch

@@ -0,0 +1,34 @@
+From 89a9306a9c24b192b9fac3b7498661428676af0e Mon Sep 17 00:00:00 2001
+From: wangzehong <wangzehong2@huawei.com>
+Date: Fri, 10 Feb 2023 09:06:21 +0800
+Subject: [PATCH] Remove monorepo requirement
+
+---
+ CMakeLists.txt | 5 -----
+ 1 file changed, 5 deletions(-)
+
+diff --git a/CMakeLists.txt b/CMakeLists.txt
+index cdd5495..11fc89b 100644
+--- a/CMakeLists.txt
++++ b/CMakeLists.txt
+@@ -1,9 +1,6 @@
+ # See https://libcxx.llvm.org/docs/BuildingLibcxx.html for instructions on how
+ # to build libcxx with CMake.
+ 
+-if (NOT IS_DIRECTORY "${CMAKE_CURRENT_LIST_DIR}/../libcxxabi")
+-  message(FATAL_ERROR "libc++ now requires being built in a monorepo layout with libcxxabi available")
+-endif()
+ 
+ #===============================================================================
+ # Setup Project
+@@ -39,8 +36,6 @@ if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR OR LIBCXX_STANDALONE_BUIL
+   set(LIBCXX_STANDALONE_BUILD 1)
+   set(LLVM_LIT_OUTPUT_DIR "${LIBCXX_BINARY_DIR}/bin")
+ 
+-  # Find the LLVM sources and simulate LLVM CMake options.
+-  include(HandleOutOfTreeLLVM)
+ endif()
+ 
+ if (LIBCXX_STANDALONE_BUILD)
+-- 
+2.33.1.windows.1

libcxx.spec

@@ -0,0 +1,71 @@
+%global debug_package %{nil}
+
+Name:           libcxx
+Version:        12.0.1
+Release:        1%{?dist}
+Summary:        LLVM "libcxx" runtime libraries
+License:        BSD
+URL:            http://llvm.org
+Source0:        https://github.com/llvm/llvm-project/releases/download/llvmorg-%{version}/libcxx-%{version}.src.tar.xz
+
+Patch0:        0001-libcxx-Remove-monorepo-requirement.patch
+BuildRequires:  gcc
+BuildRequires:  gcc-c++
+BuildRequires:  cmake
+BuildRequires:  python3
+
+%description
+The libcxx-devel package includes the libraries and header files for libcxx.
+
+    
+%package devel
+Summary:    Headers and libraries for libcxx devel
+Requires:    %{name}%{?_isa} = %{version}-%{release}
+ 
+%description devel
+%{summary}.
+
+%prep
+%autosetup -n libcxx-%{version}.src
+
+%build
+mkdir -p _build
+cd _build
+
+cmake \
+        -DCMAKE_INSTALL_PREFIX=%{_prefix} \
+        -DCMAKE_BUILD_TYPE=RelWithDebInfo \
+        -DCMAKE_C_COMPILER_TARGET=%{_arch} \
+        -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON \
+%if 0%{?__isa_bits} == 64
+        -DLLVM_LIBDIR_SUFFIX=64 \
+%else
+        -DLLVM_LIBDIR_SUFFIX= \
+%endif
+  ..
+
+%make_build
+# Copy result libc++.a
+mkdir results-static
+find . -name libc++.a -exec cp {} ./results-static \;
+cp ../src/include/atomic_support.h include/c++/v1
+cp ../src/include/refstring.h include/c++/v1
+
+%install
+cd _build
+%make_install
+install results-static/libc++.a %{buildroot}/%{_libdir}
+install include/c++/v1/atomic_support.h %{buildroot}/%{_libdir}/../include/c++/v1
+install include/c++/v1/refstring.h %{buildroot}/%{_libdir}/../include/c++/v1
+
+%files
+%{_libdir}/libc++*
+%{_prefix}/include/*
+
+%files devel
+%{_includedir}/c++/
+%{_libdir}/libc++.so
+
+%changelog
+* Tue Feb 7 2023 Wang Zehong <wangzehong2@huawei.com> - 12.0.1-1
+- update to 12.0.1-1