diff --git a/lld/COFF/Driver.cpp b/lld/COFF/Driver.cpp
index fa29d14678bf..9f352ac1c7cc 100644
--- a/lld/COFF/Driver.cpp
+++ b/lld/COFF/Driver.cpp
@@ -220,7 +220,7 @@ StringRef LinkerDriver::findDefaultEntry() {
   };
   for (auto E : Entries) {
     Symbol *Sym = Symtab.find(E[0]);
-    if (Sym && !isa<Undefined>(Sym->Body))
+    if (Sym && !isa<Undefined>(Sym->Body.load()))
       return E[1];
   }
   return "";
@@ -591,7 +591,7 @@ bool LinkerDriver::link(llvm::ArrayRef<const char *> ArgsArr) {
       Symbol *Sym = Symtab.find(From);
       if (!Sym)
         continue;
-      if (auto *U = dyn_cast<Undefined>(Sym->Body))
+      if (auto *U = dyn_cast<Undefined>(Sym->Body.load()))
         if (!U->WeakAlias)
           U->WeakAlias = Symtab.addUndefined(To);
     }
diff --git a/lld/COFF/SymbolTable.cpp b/lld/COFF/SymbolTable.cpp
index 44d943bf78e6..dc8758be4087 100644
--- a/lld/COFF/SymbolTable.cpp
+++ b/lld/COFF/SymbolTable.cpp
@@ -77,7 +77,7 @@ std::error_code SymbolTable::readArchives() {
   // Add archive member files to ObjectQueue that should resolve
   // existing undefined symbols.
   for (Symbol *Sym : LazySyms)
-    if (auto EC = addMemberFile(cast<Lazy>(Sym->Body)))
+    if (auto EC = addMemberFile(cast<Lazy>(Sym->Body.load())))
       return EC;
   return std::error_code();
 }
@@ -126,7 +126,7 @@ bool SymbolTable::reportRemainingUndefines(bool Resolve) {
   bool Ret = false;
   for (auto &I : Symtab) {
     Symbol *Sym = I.second;
-    auto *Undef = dyn_cast<Undefined>(Sym->Body);
+    auto *Undef = dyn_cast<Undefined>(Sym->Body.load());
     if (!Undef)
       continue;
     StringRef Name = Undef->getName();
@@ -140,10 +140,10 @@ bool SymbolTable::reportRemainingUndefines(bool Resolve) {
     // This odd rule is for compatibility with MSVC linker.
     if (Name.startswith("__imp_")) {
       Symbol *Imp = find(Name.substr(strlen("__imp_")));
-      if (Imp && isa<Defined>(Imp->Body)) {
+      if (Imp && isa<Defined>(Imp->Body.load())) {
         if (!Resolve)
           continue;
-        auto *D = cast<Defined>(Imp->Body);
+        auto *D = cast<Defined>(Imp->Body.load());
         auto *S = new (Alloc) DefinedLocalImport(Name, D);
         LocalImportChunks.push_back(S->getChunk());
         Sym->Body = S;
@@ -320,11 +320,11 @@ std::error_code SymbolTable::addCombinedLTOObject() {
     StringRef Name = Body->getName();
     Symbol *Sym = insert(Body);
 
-    if (isa<DefinedBitcode>(Sym->Body)) {
+    if (isa<DefinedBitcode>(Sym->Body.load())) {
       Sym->Body = Body;
       continue;
     }
-    if (auto *L = dyn_cast<Lazy>(Sym->Body)) {
+    if (auto *L = dyn_cast<Lazy>(Sym->Body.load())) {
       // We may see new references to runtime library symbols such as __chkstk
       // here. These symbols must be wholly defined in non-bitcode files.
       if (auto EC = addMemberFile(L))
diff --git a/lld/COFF/Symbols.h b/lld/COFF/Symbols.h
index 2c12af263ecd..8694b83247ef 100644
--- a/lld/COFF/Symbols.h
+++ b/lld/COFF/Symbols.h
@@ -16,6 +16,7 @@
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/Object/Archive.h"
 #include "llvm/Object/COFF.h"
+#include <atomic>
 #include <memory>
 #include <vector>
 
@@ -38,7 +39,7 @@ class SymbolBody;
 // The resolver updates SymbolBody pointers as it resolves symbols.
 struct Symbol {
   explicit Symbol(SymbolBody *P) : Body(P) {}
-  SymbolBody *Body;
+  std::atomic<SymbolBody *> Body;
 };
 
 // The base class for real symbol classes.
@@ -80,7 +81,7 @@ public:
   // has chosen the object among other objects having the same name,
   // you can access P->Backref->Body to get the resolver's result.
   void setBackref(Symbol *P) { Backref = P; }
-  SymbolBody *repl() { return Backref ? Backref->Body : this; }
+  SymbolBody *repl() { return Backref ? Backref->Body.load() : this; }
 
   // Decides which symbol should "win" in the symbol table, this or
   // the Other. Returns 1 if this wins, -1 if the Other wins, or 0 if
diff --git a/lld/COFF/Writer.cpp b/lld/COFF/Writer.cpp
index 062f63111429..8814a4df79ff 100644
--- a/lld/COFF/Writer.cpp
+++ b/lld/COFF/Writer.cpp
@@ -243,7 +243,8 @@ void Writer::createImportTables() {
       Sec->addChunk(C);
   }
   if (!DelayIdata.empty()) {
-    Defined *Helper = cast<Defined>(Symtab->find("__delayLoadHelper2")->Body);
+    Symbol *Sym = Symtab->find("__delayLoadHelper2");
+    Defined *Helper = cast<Defined>(Sym->Body.load());
     DelayIdata.create(Helper);
     OutputSection *Sec = createSection(".didat");
     for (Chunk *C : DelayIdata.getChunks())
@@ -535,7 +536,7 @@ OutputSection *Writer::createSection(StringRef Name) {
 // Dest is .reloc section. Add contents to that section.
 void Writer::addBaserels(OutputSection *Dest) {
   std::vector<uint32_t> V;
-  Defined *ImageBase = cast<Defined>(Symtab->find("__ImageBase")->Body);
+  Defined *ImageBase = cast<Defined>(Symtab->find("__ImageBase")->Body.load());
   for (OutputSection *Sec : OutputSections) {
     if (Sec == Dest)
       continue;