diff --git a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
--- a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
+++ b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
@@ -646,15 +646,20 @@
   Index.addGlobalValueSummary(V, std::move(GVarSummary));
 }
 
-static void
-computeAliasSummary(ModuleSummaryIndex &Index, const GlobalAlias &A,
-                    DenseSet<GlobalValue::GUID> &CantBePromoted) {
+static void computeAliasSummary(ModuleSummaryIndex &Index, const GlobalAlias &A,
+                                DenseSet<GlobalValue::GUID> &CantBePromoted) {
+  auto *Aliasee = A.getAliaseeObject();
+
+  // Skip summary for indirect function aliases as summary for aliasee will not
+  // be emitted.
+  if (isa<GlobalIFunc>(Aliasee))
+    return;
+
   bool NonRenamableLocal = isNonRenamableLocal(A);
   GlobalValueSummary::GVFlags Flags(
       A.getLinkage(), A.getVisibility(), NonRenamableLocal,
       /* Live = */ false, A.isDSOLocal(), A.canBeOmittedFromSymbolTable());
   auto AS = std::make_unique<AliasSummary>(Flags);
-  auto *Aliasee = A.getAliaseeObject();
   auto AliaseeVI = Index.getValueInfo(Aliasee->getGUID());
   assert(AliaseeVI && "Alias expects aliasee summary to be available");
   assert(AliaseeVI.getSummaryList().size() == 1 &&
@@ -811,6 +816,12 @@
   for (const GlobalAlias &A : M.aliases())
     computeAliasSummary(Index, A, CantBePromoted);
 
+  // Iterate through ifuncs, set their resolvers all alive.
+  for (const GlobalIFunc &I : M.ifuncs()) {
+    const GlobalValue &GV = *dyn_cast<GlobalValue>(I.getResolver());
+    Index.getGlobalValueSummary(GV)->setLive(true);
+  }
+
   for (auto *V : LocalsUsed) {
     auto *Summary = Index.getGlobalValueSummary(*V);
     assert(Summary && "Missing summary for global value");
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -4103,8 +4103,9 @@
 
   for (const GlobalAlias &A : M.aliases()) {
     auto *Aliasee = A.getAliaseeObject();
-    if (!Aliasee->hasName())
-      // Nameless function don't have an entry in the summary, skip it.
+    // IFunc function and Nameless function don't have an entry in the
+    // summary, skip it.
+    if (!Aliasee->hasName() || isa<GlobalIFunc>(Aliasee))
       continue;
     auto AliasId = VE.getValueID(&A);
     auto AliaseeId = VE.getValueID(Aliasee);
diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp
--- a/llvm/lib/Transforms/IPO/FunctionImport.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp
@@ -1169,10 +1169,13 @@
         // recorded in the index using the original name.
         // FIXME: This may not be needed once PR27866 is fixed.
         GS = DefinedGlobals.find(GlobalValue::getGUID(OrigName));
-        assert(GS != DefinedGlobals.end());
       }
     }
-    return !GlobalValue::isLocalLinkage(GS->second->linkage());
+    // It maybe the case that GV is on a chain of an ifunc, its alias and
+    // subsequent aliases. In this case, the summary for the value is not
+    // available.
+    return GS == DefinedGlobals.end() ||
+           !GlobalValue::isLocalLinkage(GS->second->linkage());
   };
 
   // FIXME: See if we can just internalize directly here via linkage changes
diff --git a/llvm/lib/Transforms/Utils/FunctionImportUtils.cpp b/llvm/lib/Transforms/Utils/FunctionImportUtils.cpp
--- a/llvm/lib/Transforms/Utils/FunctionImportUtils.cpp
+++ b/llvm/lib/Transforms/Utils/FunctionImportUtils.cpp
@@ -59,7 +59,13 @@
   // in this module.
   auto Summary = ImportIndex.findSummaryInModule(
       VI, SGV->getParent()->getModuleIdentifier());
-  assert(Summary && "Missing summary for global value when exporting");
+
+  // It maybe the case that SGV is on a chain of an ifunc, its alias and
+  // subsequent aliases. In this case, the summary for the value is not
+  // available.
+  if (!Summary)
+    return false;
+
   auto Linkage = Summary->linkage();
   if (!GlobalValue::isLocalLinkage(Linkage)) {
     assert(!isNonRenamableLocal(*SGV) &&
diff --git a/llvm/test/LTO/Resolution/X86/alias-indirect-function-lto.ll b/llvm/test/LTO/Resolution/X86/alias-indirect-function-lto.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/LTO/Resolution/X86/alias-indirect-function-lto.ll
@@ -0,0 +1,31 @@
+; RUN: opt -module-summary -o %t.bc %s
+; RUN: llvm-lto2 run %t.bc -r %t.bc,foo,px -r %t.bc,bar,px -r %t.bc,baz,px -r %t.bc,qux,px -r %t.bc,grault,px -o %t2
+; RUN: llvm-nm %t2.1 | FileCheck %s
+; CHECK: i bar
+; CHECK: i baz
+; CHECK: i foo
+; CHECK: t foo_resolver
+; CHECK: i grault
+; CHECK: i quuz
+; CHECK: i qux
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@foo = ifunc i32 (i32), i32 (i32)* ()* @foo_resolver
+
+define internal i32 (i32)* @foo_resolver() {
+entry:
+  ret i32 (i32)* null
+}
+
+@bar = alias i32 (i32), i32 (i32)* @foo
+@baz = weak alias i32 (i32), i32 (i32)* @foo
+@qux = alias i32 (i32), i32 (i32)* @bar
+
+@quux = internal alias i32 (i32)* (), i32 (i32)* ()* @foo_resolver
+@quuz = internal ifunc i32 (i32), i32 (i32)* ()* @quux
+@corge = internal alias i32 (i32), i32 (i32)* @quuz
+@grault = alias i32 (i32), i32 (i32)* @corge
+
+; no crash