Merging r343753:

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r343753 | phosek | 2018-10-03 22:38:53 -0700 (Wed, 03 Oct 2018) | 7 lines

[CMake] Use just basename when copying C++ ABI headers

This avoids duplicate directories when the filename includes path.

Fixes PR39145

Differential Revision: https://reviews.llvm.org/D52762
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git-svn-id: https://llvm.org/svn/llvm-project/libcxx/branches/release_70@348322 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/cmake/Modules/HandleLibCXXABI.cmake b/cmake/Modules/HandleLibCXXABI.cmake
index ef3b4f5..1c19d7e 100644
--- a/cmake/Modules/HandleLibCXXABI.cmake
+++ b/cmake/Modules/HandleLibCXXABI.cmake
@@ -41,7 +41,7 @@
         get_filename_component(ifile ${fpath} NAME)
         set(src ${incpath}/${fpath})
 
-        set(dst ${LIBCXX_BINARY_INCLUDE_DIR}/${dstdir}/${fpath})
+        set(dst ${LIBCXX_BINARY_INCLUDE_DIR}/${dstdir}/${ifile})
         add_custom_command(OUTPUT ${dst}
             DEPENDS ${src}
             COMMAND ${CMAKE_COMMAND} -E copy_if_different ${src} ${dst}