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

[Thurston Dang via cfe-commits]

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@@ -68,6 +68,8 @@ static const SanitizerMask TrappingSupported =
     SanitizerKind::ImplicitConversion | SanitizerKind::Nullability |
     SanitizerKind::LocalBounds | SanitizerKind::CFI |
     SanitizerKind::FloatDivideByZero | SanitizerKind::ObjCCast;
+static const SanitizerMask MergeDefault = SanitizerKind::Undefined;
+static const SanitizerMask MergeSupported = SanitizerKind::Undefined;
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thurstond wrote:

Removed

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