Index: llvm/lib/LTO/LTO.cpp
===================================================================
--- llvm/lib/LTO/LTO.cpp
+++ llvm/lib/LTO/LTO.cpp
@@ -228,6 +228,55 @@
       Hasher.update(FileOrErr.get()->getBuffer());
   }
 
+  // Include the hashes of all members of cfiFunctionDefs and cfiFunctionDecls
+  // that are referenced or defined in this module.
+  DenseMap<GlobalValue::GUID, bool> UsedCfiDefs;
+  DenseMap<GlobalValue::GUID, bool> UsedCfiDecls;
+  unsigned UsedCfiDefsCount = 0;
+  unsigned UsedCfiDeclsCount = 0;
+
+  for (const std::string& Name : Index.cfiFunctionDefs())
+    UsedCfiDefs[GlobalValue::getGUID(Name)] = false;
+  for (const std::string& Name : Index.cfiFunctionDecls())
+    UsedCfiDecls[GlobalValue::getGUID(Name)] = false;
+
+  auto AddUsedCfiGlobal = [&](GlobalValue::GUID ValueGUID) {
+    auto DefsIt = UsedCfiDefs.find(ValueGUID);
+    if (DefsIt != UsedCfiDefs.end()) {
+      UsedCfiDefsCount += !DefsIt->second;
+      DefsIt->second = true;
+    }
+    auto DeclsIt = UsedCfiDecls.find(ValueGUID);
+    if (DeclsIt != UsedCfiDecls.end()) {
+      UsedCfiDeclsCount += !DeclsIt->second;
+      DeclsIt->second = true;
+    }
+  };
+
+  for (auto &GSM : DefinedGlobals) {
+    AddUsedCfiGlobal(GSM.first);
+    for (const ValueInfo &VI : GSM.second->refs())
+      AddUsedCfiGlobal(VI.getGUID());
+  }
+
+  for (auto &ImpM : ImportList)
+    for (auto &ImpF : ImpM.second) {
+      AddUsedCfiGlobal(ImpF.first); // FIXME: is this necessary?
+      GlobalValueSummary *GS = Index.findSummaryInModule(ImpF.first, ImpM.first());
+      for (const ValueInfo &VI : GS->refs())
+        AddUsedCfiGlobal(VI.getGUID());
+    }
+
+  AddUnsigned(UsedCfiDefsCount);
+  for (auto &KV : UsedCfiDefs)
+    if (KV.second)
+      AddUint64(KV.first);
+
+  AddUnsigned(UsedCfiDeclsCount);
+  for (auto &KV : UsedCfiDecls)
+    if (KV.second)
+      AddUint64(KV.first);
+
   Key = toHex(Hasher.result());
 }
 
Index: llvm/test/ThinLTO/X86/Inputs/cache-icall-no.ll
===================================================================
--- /dev/null
+++ llvm/test/ThinLTO/X86/Inputs/cache-icall-no.ll
@@ -0,0 +1,7 @@
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @f() {
+entry:
+  ret void
+}
Index: llvm/test/ThinLTO/X86/Inputs/cache-icall-yes.ll
===================================================================
--- /dev/null
+++ llvm/test/ThinLTO/X86/Inputs/cache-icall-yes.ll
@@ -0,0 +1,9 @@
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @f() !type !0 {
+entry:
+  ret void
+}
+
+!0 = !{i64 0, !"_ZTSFvvE"}
Index: llvm/test/ThinLTO/X86/cache-icall.ll
===================================================================
--- /dev/null
+++ llvm/test/ThinLTO/X86/cache-icall.ll
@@ -0,0 +1,57 @@
+; Test that the list of CFI jumptable entries is part of ThinLTO cache key.
+
+; Linking module -yes results in f() being added to CFI jumptable; with -no it is not.
+; This affects code generated for any users of f(). Make sure that we don't pull a stale object
+; file for %t.o from the cache when -no is replaced with -yes in the link.
+
+; RUN: opt -module-hash -module-summary -thinlto-bc %s -o %t.bc
+; RUN: opt -module-hash -module-summary -thinlto-bc %p/Inputs/cache-icall-no.ll -o %t-no.bc
+; RUN: opt -module-hash -module-summary -thinlto-bc %p/Inputs/cache-icall-yes.ll -o %t-yes.bc
+
+; RUN: rm -Rf %t.cache && mkdir %t.cache
+
+; RUN: llvm-lto2 run -o %t-no.o %t.bc %t-no.bc -cache-dir %t.cache \
+; RUN:   -r=%t.bc,_start,px \
+; RUN:   -r=%t.bc,f, \
+; RUN:   -r=%t-no.bc,f,p
+
+; RUN: llvm-readelf -symbols %t-no.o.* | FileCheck %s --check-prefix=SYMBOLS-NO
+
+; RUN: llvm-lto2 run -o %t-yes.o %t.bc %t-yes.bc -cache-dir %t.cache \
+; RUN:   -r=%t.bc,_start,px \
+; RUN:   -r=%t.bc,f, \
+; RUN:   -r=%t-yes.bc,f,p
+
+; RUN: llvm-readelf -symbols %t-yes.o.* | FileCheck %s --check-prefix=SYMBOLS-YES
+
+; SYMBOLS-NO-DAG: {{FUNC .* f.cfi_jt$}}
+; SYMBOLS-NO-DAG: {{NOTYPE .* UND f.cfi_jt$}}
+
+; SYMBOLS-YES-NOT: f.cfi_jt
+; SYMBOLS-YES-DAG: {{FUNC .* f.cfi$}}
+; SYMBOLS-YES-DAG: {{NOTYPE .* UND f.cfi$}}
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define i8* @_start(void ()* %p) !type !0 {
+entry:
+  %0 = bitcast void ()* %p to i8*
+  %1 = tail call i1 @llvm.type.test(i8* %0, metadata !"_ZTSFvvE")
+  br i1 %1, label %cont, label %trap
+
+trap:                                             ; preds = %entry
+  tail call void @llvm.trap()
+  unreachable
+
+cont:                                             ; preds = %entry
+  tail call void %p()
+  ret i8* bitcast (void ()* @f to i8*)
+}
+
+declare i1 @llvm.type.test(i8*, metadata)
+declare void @llvm.trap()
+declare !type !1 void @f()
+
+!0 = !{i64 0, !"_ZTSFPvPFvvEE"}
+!1 = !{i64 0, !"_ZTSFvvE"}