[clang] [llvm] [RISCV] Implement shadow stack on shadow stack mode with Zicfiss. (PR #68075)

[Yeting Kuo via cfe-commits]

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@@ -27,6 +27,11 @@
 
 using namespace llvm;
 
+static cl::opt<bool>
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yetingk wrote:

The new commit [2830d3e](https://github.com/llvm/llvm-project/pull/68075/commits/2830d3ebf9eb9aae758740e6c38359984b8684b2) adds a new feature to replace this. In the feature, we can add clang option to pass the feature to llvm.

https://github.com/llvm/llvm-project/pull/68075