Merging r353463:

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r353463 | smeenai | 2019-02-07 21:58:04 +0100 (Thu, 07 Feb 2019) | 4 lines

[cmake] Pass LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN to NATIVE configure

We should propagate this down to host builds so that e.g. people using
an optimized tablegen can do the sub-configure successfully.
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llvm-svn: 353517

Author: zmodem

llvm/cmake/modules/CrossCompile.cmake

@@ -52,6 +52,7 @@ function(llvm_create_cross_target_internal target_name toolchain buildtype)
         -DLLVM_EXPERIMENTAL_TARGETS_TO_BUILD="${experimental_targets_to_build_arg}"
         -DLLVM_DEFAULT_TARGET_TRIPLE="${TARGET_TRIPLE}"
         -DLLVM_TARGET_ARCH="${LLVM_TARGET_ARCH}"
+        -DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN="${LLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN}"
         ${build_type_flags} ${linker_flag} ${external_clang_dir}
     WORKING_DIRECTORY ${LLVM_${target_name}_BUILD}
     DEPENDS CREATE_LLVM_${target_name}