[clang] Add option -fstdlib-hardening= (PR #78763)

[Aaron Ballman via cfe-commits]

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@@ -7730,6 +7730,14 @@ def source_date_epoch : Separate<["-"], "source-date-epoch">,
 
 } // let Visibility = [CC1Option]
 
+def stdlib_hardening_EQ : Joined<["-"], "fstdlib-hardening=">,
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AaronBallman wrote:

I am worried about that -- I'm also worried about folks thinking it applies to more than libc++.

https://github.com/llvm/llvm-project/pull/78763