[PATCH] D55857: [asan] Prevent folding of globals with redzones

[Peter Collingbourne via Phabricator via llvm-commits]

pcc added inline comments.


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Comment at: llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp:2151
+    // Don't fold globals with redzones. This will cause false ODR-violation and
+    // global-buffer-overflow reports.
+    NewGlobal->setUnnamedAddr(GlobalValue::UnnamedAddr::None);
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The comment should say that asan's ODR violation detector and redzone poisoning implicitly creates a dependence on the global's address, so it is no longer valid for it to be marked unnamed_addr.


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Comment at: llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp:2203
     if (NewGlobal->hasLocalLinkage() || NewGlobal->hasLinkOnceODRLinkage() ||
         NewGlobal->hasWeakODRLinkage()) {
       ODRIndicator = ConstantExpr::getIntToPtr(ConstantInt::get(IntptrTy, -1),
----------------
Can we remove the linkonce_odr and weak_odr checks from here now?


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55857/new/

https://reviews.llvm.org/D55857