[asan] Restore ODR-violation detection on vtables

Summary:
unnamed_addr is still useful for detecting of ODR violations on vtables

Still unnamed_addr with lld and --icf=safe or --icf=all can trigger false
reports which can be avoided with --icf=none or by using private aliases
with -fsanitize-address-use-odr-indicator

Reviewers: eugenis

Reviewed By: eugenis

Subscribers: kubamracek, hiraditya, llvm-commits

Differential Revision: https://reviews.llvm.org/D55799

llvm-svn: 349555

diff --git a/compiler-rt/test/asan/TestCases/Linux/odr-vtable.cc b/compiler-rt/test/asan/TestCases/Linux/odr-vtable.cc
new file mode 100644 (file)
index 0000000..70ea4c9
--- /dev/null
+++ b/compiler-rt/test/asan/TestCases/Linux/odr-vtable.cc
@@ -0,0 +1,26 @@
+// RUN: %clangxx_asan -fno-rtti -DBUILD_SO1 -fPIC -shared %s -o %t1.so
+// RUN: %clangxx_asan -fno-rtti -DBUILD_SO2 -fPIC -shared %s -o %t2.so
+// RUN: %clangxx_asan -fno-rtti %t1.so %t2.so %s -Wl,-R. -o %t
+// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t 2>&1 | FileCheck %s
+
+struct XYZ {
+  virtual void foo();
+};
+
+#if defined(BUILD_SO1)
+
+void XYZ::foo() {}
+
+#elif defined(BUILD_SO2)
+
+void XYZ::foo() {}
+
+#else
+
+int main() {}
+
+#endif
+
+// CHECK: AddressSanitizer: odr-violation
+// CHECK-NEXT: 'vtable for XYZ'
+// CHECK-NEXT: 'vtable for XYZ'

diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 769cd23..2ede467 100644 (file)
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -2199,8 +2199,8 @@ bool AddressSanitizerModule::InstrumentGlobals(IRBuilder<> &IRB, Module &M, bool
 
     // ODR check is not useful for the following, but we see false reports
     // caused by linker optimizations.
-    if (NewGlobal->hasLocalLinkage() || NewGlobal->hasGlobalUnnamedAddr() ||
-        NewGlobal->hasLinkOnceODRLinkage() || NewGlobal->hasWeakODRLinkage()) {
+    if (NewGlobal->hasLocalLinkage() || NewGlobal->hasLinkOnceODRLinkage() ||
+        NewGlobal->hasWeakODRLinkage()) {
       ODRIndicator = ConstantExpr::getIntToPtr(ConstantInt::get(IntptrTy, -1),
                                                IRB.getInt8PtrTy());
     } else if (UseOdrIndicator) {

diff --git a/llvm/test/Instrumentation/AddressSanitizer/odr-check-ignore.ll b/llvm/test/Instrumentation/AddressSanitizer/odr-check-ignore.ll
index 3a9e614..cf48d19 100644 (file)
--- a/llvm/test/Instrumentation/AddressSanitizer/odr-check-ignore.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/odr-check-ignore.ll
@@ -14,4 +14,4 @@ target triple = "x86_64-unknown-linux-gnu"
 
 ; CHECK: @__asan_global_c = private global { i64, i64, i64, i64, i64, i64, i64, i64 } { i64 ptrtoint ({ [2 x i32], [56 x i8] }* @c to i64), i64 8, i64 64, i64 ptrtoint ([2 x i8]* @___asan_gen_.3 to i64), i64 ptrtoint ([8 x i8]* @___asan_gen_ to i64), i64 0, i64 0, i64 -1 }
 
-; CHECK: @__asan_global_d = private global { i64, i64, i64, i64, i64, i64, i64, i64 } { i64 ptrtoint ({ [2 x i32], [56 x i8] }* @d to i64), i64 8, i64 64, i64 ptrtoint ([2 x i8]* @___asan_gen_.4 to i64), i64 ptrtoint ([8 x i8]* @___asan_gen_ to i64), i64 0, i64 0, i64 -1 }
+; CHECK: @__asan_global_d = private global { i64, i64, i64, i64, i64, i64, i64, i64 } { i64 ptrtoint ({ [2 x i32], [56 x i8] }* @d to i64), i64 8, i64 64, i64 ptrtoint ([2 x i8]* @___asan_gen_.4 to i64), i64 ptrtoint ([8 x i8]* @___asan_gen_ to i64), i64 0, i64 0, i64 0 }