[lld] [ELF] Add support for PT_OPENBSD_NOBTCFI (PR #120005)

[Fangrui Song via llvm-commits]

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@@ -1487,6 +1487,7 @@ static void readConfigs(Ctx &ctx, opt::InputArgList &args) {
       args, "keep-text-section-prefix", "nokeep-text-section-prefix", false);
   ctx.arg.zLrodataAfterBss =
       getZFlag(args, "lrodata-after-bss", "nolrodata-after-bss", false);
+  ctx.arg.zNoBtCfi = hasZOption(args, "nobtcfi");
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MaskRay wrote:

Initialize the variable to false. Move this to setConfigs and only do it when osabi is openbsd.

https://github.com/llvm/llvm-project/pull/120005