[llvm] build_llvm_release.bat: add tarball export to x64 release (PR #79840)

[via llvm-commits]

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@@ -287,7 +287,16 @@ ninja check-sanitizer || ninja check-sanitizer || ninja check-sanitizer || exit
 ninja check-clang-tools || ninja check-clang-tools || ninja check-clang-tools || exit /b 1
 ninja check-clangd || ninja check-clangd || ninja check-clangd || exit /b 1
 ninja package || exit /b 1
+
+:: generate tarball with install toolchain only off
+set filename=clang+llvm-%version%-x86_64-pc-windows-msvc
+cmake -GNinja %cmake_flags% -DLLVM_INSTALL_TOOLCHAIN_ONLY=OFF ^
+  -DCMAKE_INSTALL_PREFIX=%build_dir%/%filename% ..\llvm-project\llvm || exit /b 1
+ninja install || exit /b 1
+:: check llvm_config is present & returns something
+%build_dir%/%filename%/bin/llvm-config.exe --bindir
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zmodem wrote:

Do we need to `|| exit /b 1` to make it fail if it doesn't exist/works?

https://github.com/llvm/llvm-project/pull/79840