Index: lib/LTO/LTOBackend.cpp
===================================================================
--- lib/LTO/LTOBackend.cpp
+++ lib/LTO/LTOBackend.cpp
@@ -401,12 +401,27 @@
 
 static void dropDeadSymbols(Module &Mod, const GVSummaryMapTy &DefinedGlobals,
                             const ModuleSummaryIndex &Index) {
+  std::vector<GlobalValue*> DeadGVs;
   for (auto &GV : Mod) {
     auto It = DefinedGlobals.find(GV.getGUID());
     if (It == DefinedGlobals.end())
       continue;
-    if (!Index.isGlobalValueLive(It->second))
+    if (!Index.isGlobalValueLive(It->second)) {
       convertToDeclaration(GV);
+      DeadGVs.push_back(&GV);
+    }
+  }
+  // Now that all dead bodies have been dropped, delete the actual objects
+  // themselves when possible.
+  for (GlobalValue *GV : DeadGVs) {
+    if (!GV->use_empty()) {
+      GV->removeDeadConstantUsers();
+      // References something defined in native object (this def
+      // non-prevailing), or in alias/variable (can't be dropped yet).
+      if (!GV->use_empty())
+        continue;
+    }
+    GV->eraseFromParent();
   }
 }
 
Index: test/ThinLTO/X86/deadstrip.ll
===================================================================
--- test/ThinLTO/X86/deadstrip.ll
+++ test/ThinLTO/X86/deadstrip.ll
@@ -50,7 +50,7 @@
 ; LTO2: define internal void @_GLOBAL__I_a()
 ; LTO2: define internal void @bar() {
 ; LTO2: define internal void @bar_internal()
-; LTO2: declare dso_local void @dead_func()
+; LTO2-NOT: @dead_func()
 ; LTO2-NOT: available_externally {{.*}} @baz()
 
 ; Make sure we didn't internalize @boo, which is reachable via
Index: test/Transforms/PGOProfile/thinlto_samplepgo_icp_droppeddead.ll
===================================================================
--- /dev/null
+++ test/Transforms/PGOProfile/thinlto_samplepgo_icp_droppeddead.ll
@@ -0,0 +1,71 @@
+; REQUIRES: x86-registered-target
+
+; RUN: opt -module-summary %s -o %t.bc
+
+; Tests that with dead stripping in the thin link enabled (default), we do not
+; promote to target of the dropped dead symbol _ZL3foov. This can happen with a
+; sample profile collected for one binary used to  optimize for another binary.
+; RUN: llvm-lto2 run -save-temps -o %t2 %t.bc -r %t.bc,fptr,plx \
+; RUN:		-r %t.bc,main,plx -r %t.bc,_ZL3foov,l
+; RUN: llvm-dis < %t2.1.4.opt.bc | FileCheck %s --check-prefix=OPT
+; RUN: llvm-lto2 run -save-temps -o %t2 %t.bc -r %t.bc,fptr,plx \
+; RUN: 		-r %t.bc,main,plx -r %t.bc,_ZL3foov,l -compute-dead=false
+; RUN: llvm-dis < %t2.1.4.opt.bc | FileCheck %s --check-prefix=OPT-NODEAD
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+@fptr = local_unnamed_addr global void ()* null, align 8
+
+define void @_ZL3foov() #1 {
+entry:
+  ret void
+}
+
+define i32 @main() local_unnamed_addr #0 !prof !34 {
+entry:
+  %0 = load void ()*, void ()** @fptr, align 8
+; OPT-NOT: label %if.false.orig_indirect
+; OPT-NODEAD: br i1 %{{[0-9]+}}, label %if.end.icp, label %if.false.orig_indirect
+  tail call void %0(), !prof !40
+  ret i32 0
+}
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3,!4}
+!llvm.ident = !{!31}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 5.0.0 (trunk 297016)", isOptimized: true, runtimeVersion: 0, emissionKind: NoDebug, enums: !2)
+!1 = !DIFile(filename: "main.cc", directory: ".")
+!2 = !{}
+!3 = !{i32 2, !"Debug Info Version", i32 3}
+!4 = !{i32 1, !"ProfileSummary", !5}
+!5 = !{!6, !7, !8, !9, !10, !11, !12, !13}
+!6 = !{!"ProfileFormat", !"SampleProfile"}
+!7 = !{!"TotalCount", i64 3003}
+!8 = !{!"MaxCount", i64 3000}
+!9 = !{!"MaxInternalCount", i64 0}
+!10 = !{!"MaxFunctionCount", i64 0}
+!11 = !{!"NumCounts", i64 3}
+!12 = !{!"NumFunctions", i64 1}
+!13 = !{!"DetailedSummary", !14}
+!14 = !{!15, !16, !17, !18, !19, !20, !20, !21, !21, !22, !23, !24, !25, !26, !27, !28, !29, !30}
+!15 = !{i32 10000, i64 3000, i32 1}
+!16 = !{i32 100000, i64 3000, i32 1}
+!17 = !{i32 200000, i64 3000, i32 1}
+!18 = !{i32 300000, i64 3000, i32 1}
+!19 = !{i32 400000, i64 3000, i32 1}
+!20 = !{i32 500000, i64 3000, i32 1}
+!21 = !{i32 600000, i64 3000, i32 1}
+!22 = !{i32 700000, i64 3000, i32 1}
+!23 = !{i32 800000, i64 3000, i32 1}
+!24 = !{i32 900000, i64 3000, i32 1}
+!25 = !{i32 950000, i64 3000, i32 1}
+!26 = !{i32 990000, i64 3000, i32 1}
+!27 = !{i32 999000, i64 3000, i32 1}
+!28 = !{i32 999900, i64 2, i32 2}
+!29 = !{i32 999990, i64 2, i32 2}
+!30 = !{i32 999999, i64 2, i32 2}
+!31 = !{!"clang version 5.0.0 (trunk 297016)"}
+!34 = !{!"function_entry_count", i64 1}
+!40 = !{!"VP", i32 0, i64 3000, i64 -8789629626369651636, i64 3000}
Index: test/tools/gold/X86/global_with_section.ll
===================================================================
--- test/tools/gold/X86/global_with_section.ll
+++ test/tools/gold/X86/global_with_section.ll
@@ -59,7 +59,7 @@
 ; the expected internalization.
 ; CHECK2-REGULARLTO-DAG: define internal void @deadfunc_with_nonC_section() section ".nonCsection"
 ; Check dead function converted to declaration.
-; CHECK-THINLTO-DAG: declare dso_local void @deadfunc_with_nonC_section() section ".nonCsection"
+; CHECK-THINLTO-NOT: @deadfunc_with_nonC_section()
 define void @deadfunc_with_nonC_section() section ".nonCsection" {
   call void @deadfunc2_called_from_nonC_section()
   ret void
@@ -78,5 +78,5 @@
 ; are getting the expected internalization.
 ; CHECK2-REGULARLTO: define internal void @deadfunc2_called_from_nonC_section
 ; Check dead function converted to declaration.
-; CHECK2-THINLTO: declare dso_local void @deadfunc2_called_from_nonC_section
+; CHECK2-THINLTO-NOT: @deadfunc2_called_from_nonC_section
 declare void @deadfunc2_called_from_nonC_section()