[llvm] 12489b5 - llvm-dwarfdump: Fix UB (unsequenced writes) introduced in e0fd87cc64d5

[David Blaikie via llvm-commits]

Author: David Blaikie
Date: 2020-04-19T21:35:04-07:00
New Revision: 12489b54746339b7304e79a34739e383ab186aaa

URL: https://github.com/llvm/llvm-project/commit/12489b54746339b7304e79a34739e383ab186aaa
DIFF: https://github.com/llvm/llvm-project/commit/12489b54746339b7304e79a34739e383ab186aaa.diff

LOG: llvm-dwarfdump: Fix UB (unsequenced writes) introduced in e0fd87cc64d5

Unsequenced write due to "x &= f()" where 'f()' modifies 'x'.

Detected by the llvm-clang-x86_64-expensive-checks-win buildbot.
Investigated/identified by Galina - thanks!

Added: 
    

Modified: 
    llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp

Removed: 
    


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diff  --git a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
index 31de753e7a19..9cae4dc3d5b3 100644
--- a/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
+++ b/llvm/tools/llvm-dwarfdump/llvm-dwarfdump.cpp
@@ -506,7 +506,8 @@ static bool handleBuffer(StringRef Filename, MemoryBufferRef Buffer,
     if (filterArch(*Obj)) {
       std::unique_ptr<DWARFContext> DICtx =
           DWARFContext::create(*Obj, nullptr, "", RecoverableErrorHandler);
-      Result &= HandleObj(*Obj, *DICtx, Filename, OS);
+      if (!HandleObj(*Obj, *DICtx, Filename, OS))
+        Result = false;
     }
   }
   else if (auto *Fat = dyn_cast<MachOUniversalBinary>(BinOrErr->get()))
@@ -518,14 +519,16 @@ static bool handleBuffer(StringRef Filename, MemoryBufferRef Buffer,
         if (filterArch(Obj)) {
           std::unique_ptr<DWARFContext> DICtx =
               DWARFContext::create(Obj, nullptr, "", RecoverableErrorHandler);
-          Result &= HandleObj(Obj, *DICtx, ObjName, OS);
+          if (!HandleObj(Obj, *DICtx, ObjName, OS))
+            Result = false;
         }
         continue;
       } else
         consumeError(MachOOrErr.takeError());
       if (auto ArchiveOrErr = ObjForArch.getAsArchive()) {
         error(ObjName, errorToErrorCode(ArchiveOrErr.takeError()));
-        Result &= handleArchive(ObjName, *ArchiveOrErr.get(), HandleObj, OS);
+        if (!handleArchive(ObjName, *ArchiveOrErr.get(), HandleObj, OS))
+          Result = false;
         continue;
       } else
         consumeError(ArchiveOrErr.takeError());