[clang] [llvm] [MTE] Add an attribute to opt-in memory tagging of global variables while using fsanitize=memtag-globals (#166380) (PR #168535)

[Florian Mayer via llvm-commits]

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@@ -3908,6 +3908,12 @@ def X86ForceAlignArgPointer : InheritableAttr, TargetSpecificAttr<TargetAnyX86>
   let Documentation = [X86ForceAlignArgPointerDocs];
 }
 
+def SectionMemtag : InheritableAttr {
+  let Spellings = [ClangGCC<"section_memtag">];
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fmayer wrote:

We could reuse `force_memtag` to e.g. force the stack instrumentation to not use stack safety analysis for a particular local variable and always tag it with MTE.

https://github.com/llvm/llvm-project/pull/168535