[lld] [LLD] Make lld define __eh_frame_* symbols (PR #162638)

[via llvm-commits]

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@@ -2269,6 +2269,12 @@ template <class ELFT> void Writer<ELFT>::addStartEndSymbols() {
   define("__preinit_array_start", "__preinit_array_end", ctx.out.preinitArray);
   define("__init_array_start", "__init_array_end", ctx.out.initArray);
   define("__fini_array_start", "__fini_array_end", ctx.out.finiArray);
+  // Define __eh_frame_* symbols, libunwind needs these symbols.
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quic-k wrote:

yes, with this patch we won't have to use that fragment just to provide these symbols

IIUC __exidx_start/end are ARM's version of __eh_frame_start/end, right?
does lld define them?

https://github.com/llvm/llvm-project/pull/162638