Author: Fangrui Song Date: 2020-12-05T17:51:10-08:00 New Revision: 5582a7987662a92eda5d883b88fc4586e755acf5
URL: https://github.com/llvm/llvm-project/commit/5582a7987662a92eda5d883b88fc4586e755acf5 DIFF: https://github.com/llvm/llvm-project/commit/5582a7987662a92eda5d883b88fc4586e755acf5.diff LOG: [TargetMachine] Set dso_local if asan is detected AddressSanitizer instrumentation does not set dso_local on non-thread-local global variables in -fno-pic and it seems to rely on implied dso_local to work. Add a hack until we have fixed AddressSanitizer to call setDSOLocal() as appropriate. Thanks to Vitaly Buka for reporting the issue and suggesting the way to detect asan. Added: Modified: llvm/lib/Target/TargetMachine.cpp Removed: ################################################################################ diff --git a/llvm/lib/Target/TargetMachine.cpp b/llvm/lib/Target/TargetMachine.cpp index ad0e90125258..f214a47ba702 100644 --- a/llvm/lib/Target/TargetMachine.cpp +++ b/llvm/lib/Target/TargetMachine.cpp @@ -163,6 +163,11 @@ bool TargetMachine::shouldAssumeDSOLocal(const Module &M, // If the symbol is defined, it cannot be preempted. if (!GV->isDeclarationForLinker()) return true; + // FIXME asan does not call setDSOLocal appropriately. Fix asan and delete + // the hack. + if (RM == Reloc::Static && !GV->isThreadLocal() && + M.getFunction("asan.module_ctor")) + return true; } else if (TT.isOSBinFormatELF()) { // If dso_local allows AsmPrinter::getSymbolPreferLocal to use a local // alias, set the flag. We cannot set dso_local for other global values, _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
