diff --git a/llvm/lib/Object/IRSymtab.cpp b/llvm/lib/Object/IRSymtab.cpp
--- a/llvm/lib/Object/IRSymtab.cpp
+++ b/llvm/lib/Object/IRSymtab.cpp
@@ -45,6 +45,10 @@
 #define HANDLE_LIBCALL(code, name) name,
 #include "llvm/IR/RuntimeLibcalls.def"
 #undef HANDLE_LIBCALL
+    // This is a global variable defined by the user, so put it here instead of
+    // in RuntimeLibcalls.def.
+    // TODO: Are there similar such variables?
+    "__stack_chk_guard"
 };
 
 namespace {
diff --git a/llvm/test/ThinLTO/X86/builtin-nostrip.ll b/llvm/test/ThinLTO/X86/builtin-nostrip.ll
--- a/llvm/test/ThinLTO/X86/builtin-nostrip.ll
+++ b/llvm/test/ThinLTO/X86/builtin-nostrip.ll
@@ -15,6 +15,7 @@
 ; Test new lto interface with thinlto.
 ; RUN: llvm-lto2 run %t1.bc -o %t.out -save-temps \
 ; RUN:   -r %t1.bc,bar,pl \
+; RUN:   -r %t1.bc,__stack_chk_guard,pl \
 ; RUN:   -r %t1.bc,__stack_chk_fail,pl
 ; RUN: llvm-nm %t.out.1 | FileCheck %s --check-prefix=CHECK-NM
 ;
@@ -25,7 +26,8 @@
 ; Test the new lto interface without thinlto.
 ; RUN: llvm-lto2 run %t4.bc -o %t5.out -save-temps \
 ; RUN:   -r %t4.bc,bar,pl \
-; RUN:   -r %t4.bc,__stack_chk_fail,pl 
+; RUN:   -r %t4.bc,__stack_chk_guard,pl \
+; RUN:   -r %t4.bc,__stack_chk_fail,pl
 ; RUN: llvm-nm %t5.out.0 | FileCheck %s --check-prefix=CHECK-NM
 
 ; Test the old lto interface without thinlto.  For now we need to
@@ -39,11 +41,13 @@
 ; The final binary should not contain any of the dead functions;
 ; make sure memmove and memcpy are there.
 ; CHECK-NM-NOT: bar
+; CHECK-NM-DAG: D __stack_chk_guard
 ; CHECK-NM-DAG: T __stack_chk_fail
 ; CHECK-NM-NOT: bar
 
 ; Test case for old lto without thinlto.  Hopefully these can be
 ; eliminated once the old lto interface is fixed.
+; CHECK-NM2-DAG: D __stack_chk_guard
 ; CHECK-NM2-DAG: t __stack_chk_fail
 
 target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
@@ -53,6 +57,7 @@
     ret void
 }
 
+@__stack_chk_guard = dso_local global i64 1, align 8
 
 define void @__stack_chk_fail() {
     ret void