Index: llvm/lib/LTO/LTO.cpp
===================================================================
--- llvm/lib/LTO/LTO.cpp
+++ llvm/lib/LTO/LTO.cpp
@@ -871,8 +871,8 @@
 
       GlobalValue *GV =
           RegularLTO.CombinedModule->getNamedValue(R.second.IRName);
-      // Ignore symbols defined in other partitions.
-      if (!GV || GV->hasLocalLinkage())
+      // Ignore declarations and symbols defined in other partitions.
+      if (!GV || GV->hasLocalLinkage() || GV->isDeclaration())
         continue;
       GV->setUnnamedAddr(R.second.UnnamedAddr ? GlobalValue::UnnamedAddr::Global
                                               : GlobalValue::UnnamedAddr::None);
Index: llvm/test/LTO/X86/Inputs/pr38046.m.ll
===================================================================
--- /dev/null
+++ llvm/test/LTO/X86/Inputs/pr38046.m.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"
+
+declare i32 @foo()
+
+define i32 @main(i32 %argc, i8** %argv) {
+  %call = call i32 @foo()
+  ret i32 %call
+}
Index: llvm/test/LTO/X86/pr38046.ll
===================================================================
--- /dev/null
+++ llvm/test/LTO/X86/pr38046.ll
@@ -0,0 +1,58 @@
+; RUN: rm -fr %t
+; RUN: mkdir -p %t
+; RUN: opt -module-summary -o %t/t.o %s
+; RUN: opt -o %t/m.o %S/Inputs/pr38046.m.ll
+; RUN: cd %t
+; RUN: llvm-lto2 run -save-temps -o m m.o t.o \
+; RUN:   -r=m.o,main,plx \
+; RUN:   -r=m.o,foo,l \
+; RUN:   -r=t.o,foo,pl \
+; RUN:   -r=t.o,get,pl
+; RUN: llvm-dis m.0.2.internalize.bc > /dev/null
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define i32 @foo() !dbg !17 {
+  call void @llvm.dbg.value(metadata i32 ()* @get, metadata !22, metadata !DIExpression()), !dbg !24
+  ret i32 0, !dbg !25
+}
+
+define i32 @get() !dbg !26 {
+  ret i32 0, !dbg !27
+}
+
+declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!12, !13, !14, !15}
+!llvm.ident = !{!16}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 7.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !{}, retainedTypes: !3, globals: !{})
+!1 = !DIFile(filename: "t.cc", directory: "/tmp/t")
+!2 = !{}
+!3 = !{!4}
+!4 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!5 = !DIFile(filename: "./t.h", directory: "/tmp/t")
+!6 = !DISubprogram(name: "get", linkageName: "get", scope: !0, file: !5, line: 3, type: !7, isLocal: false, isDefinition: false, scopeLine: 3, flags: DIFlagPublic | DIFlagPrototyped | DIFlagStaticMember, isOptimized: true)
+!7 = !DISubroutineType(types: !8)
+!8 = !{!4}
+!9 = !DISubprogram(name: "foo", linkageName: "foo", scope: !0, file: !5, line: 4, type: !10, isLocal: false, isDefinition: false, scopeLine: 4, flags: DIFlagPublic | DIFlagPrototyped, isOptimized: true)
+!10 = !DISubroutineType(types: !11)
+!11 = !{!4}
+!12 = !{i32 2, !"Dwarf Version", i32 4}
+!13 = !{i32 2, !"Debug Info Version", i32 3}
+!14 = !{i32 1, !"wchar_size", i32 4}
+!15 = !{i32 1, !"ThinLTO", i32 0}
+!16 = !{!"clang version 7.0.0 "}
+!17 = distinct !DISubprogram(name: "foo", linkageName: "foo", scope: !0, file: !1, line: 5, type: !10, isLocal: false, isDefinition: true, scopeLine: 5, flags: DIFlagPrototyped, isOptimized: true, unit: !0, declaration: !9, retainedNodes: !{})
+!18 = distinct !DISubprogram(name: "do", linkageName: "do", scope: !5, file: !5, line: 10, type: !19, isLocal: false, isDefinition: true, scopeLine: 10, flags: DIFlagPrototyped, isOptimized: true, unit: !0, templateParams: !{}, retainedNodes: !21)
+!19 = !DISubroutineType(types: !20)
+!20 = !{!4}
+!21 = !{!22}
+!22 = !DILocalVariable(name: "get", scope: !18, file: !5, line: 11, type: !4)
+!23 = distinct !DILocation(line: 6, column: 21, scope: !17)
+!24 = !DILocation(line: 11, column: 14, scope: !18, inlinedAt: !23)
+!25 = !DILocation(line: 12, column: 1, scope: !17)
+!26 = distinct !DISubprogram(name: "get", linkageName: "get", scope: !0, file: !1, line: 14, type: !7, isLocal: false, isDefinition: true, scopeLine: 14, flags: DIFlagPrototyped, isOptimized: true, unit: !0, declaration: !6, retainedNodes: !2)
+!27 = !DILocation(line: 15, column: 3, scope: !26)