[lld] Fix lld crash wrt generated thunks growing away from the patched code (PR #170495)

[Tarcísio Fischer via llvm-commits]

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@@ -399,6 +401,12 @@ Patch843419Section::Patch843419Section(Ctx &ctx, InputSection *p, uint64_t off)
       ctx, ctx.saver.save("__CortexA53843419_" + utohexstr(getLDSTAddr())),
       STT_FUNC, 0, getSize(), *this);
   addSyntheticLocal(ctx, ctx.saver.save("$x"), STT_NOTYPE, 0, 0, *this);
+  retSym = addSyntheticLocal(
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tarcisiofischer wrote:

I removed the return symbol, so I'm resolving this, but please feel free to re-open (or create a new one) if you think the new solution isn't good enough!

https://github.com/llvm/llvm-project/pull/170495