Libunwind w/ static linkage (adapter from Yves Delley's)

0002-explicitly-specify-location-of-libunwind-in-static-b.patch

diff --git a/libcxxabi/src/CMakeLists.txt b/libcxxabi/src/CMakeLists.txt
index b38973b0b17..a06c9cba498 100644
--- a/libcxxabi/src/CMakeLists.txt
+++ b/libcxxabi/src/CMakeLists.txt
@@ -84,9 +84,11 @@ if (LIBCXXABI_USE_LLVM_UNWINDER)
   if (NOT LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY AND (TARGET unwind_shared OR HAVE_LIBUNWIND))
     list(APPEND LIBCXXABI_STATIC_LIBRARIES unwind_shared)
   elseif (LIBCXXABI_STATICALLY_LINK_UNWINDER_IN_STATIC_LIBRARY AND (TARGET unwind_static OR HAVE_LIBUNWIND))
-      # We handle this by directly merging libunwind objects into libc++abi.
+    # We handle this by directly merging libunwind objects into libc++abi.
+    set(LIBUNWIND_STATIC_LIBRARY_FILE "$<TARGET_LINKER_FILE:unwind_static>")
   else()
     list(APPEND LIBCXXABI_STATIC_LIBRARIES unwind)
+    set(LIBUNWIND_STATIC_LIBRARY_FILE libunwind.a ${LIBCXXABI_LIBUNWIND_LINK_FLAGS})
   endif()
 else()
   add_library_flags_if(LIBCXXABI_HAS_GCC_S_LIB gcc_s)
@@ -264,7 +266,7 @@ if (LIBCXXABI_ENABLE_STATIC)
         --ar "${CMAKE_AR}"
         ${MERGE_ARCHIVES_LIBTOOL}
         "$<TARGET_LINKER_FILE:cxxabi_static>"
-        "$<TARGET_LINKER_FILE:unwind_static>"
+        ${LIBUNWIND_STATIC_LIBRARY_FILE}
       WORKING_DIRECTORY ${LIBCXXABI_BUILD_DIR}
     )
   endif()