[clang] [ubsan] Add -fsanitize-nonmerged-handlers (and -fno-sanitize-nonmerged-handlers) (PR #120464)

[Vitaly Buka via cfe-commits]

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@@ -2548,6 +2548,14 @@ def fsanitize_trap_EQ : CommaJoined<["-"], "fsanitize-trap=">, Group<f_clang_Gro
 def fno_sanitize_trap_EQ : CommaJoined<["-"], "fno-sanitize-trap=">, Group<f_clang_Group>,
                            Visibility<[ClangOption, CLOption]>,
                            HelpText<"Disable trapping for specified sanitizers">;
+def fsanitize_nonmerged_handlers_EQ
+    : CommaJoined<["-"], "fsanitize-nonmerged-handlers=">,
+      Group<f_clang_Group>,
+      HelpText<"Enable non-merged handlers for specified sanitizers">;
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vitalybuka wrote:

There are non-_EQ version for trap and recover, we probably want them for consistency

https://github.com/llvm/llvm-project/pull/120464