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

[Peter Smith 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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smithp35 wrote:

The __eh_frame_* symbols are equivalent to `__exidx_start` and `__exidx_end` so this seems reasonable to me.

llvm libunwind reference with suggested linker script fragment (https://github.com/llvm/llvm-project/blob/main/libunwind/src/AddressSpace.hpp#L75) 


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