Index: lib/Transforms/Instrumentation/InstrProfiling.cpp
===================================================================
--- lib/Transforms/Instrumentation/InstrProfiling.cpp
+++ lib/Transforms/Instrumentation/InstrProfiling.cpp
@@ -196,13 +196,17 @@
   if (It != RegionCounters.end())
     return It->second;
 
-  // Move the name variable to the right section. Make sure it is placed in the
-  // same comdat as its associated function. Otherwise, we may get multiple
-  // counters for the same function in certain cases.
+  // Move the name variable to the right section. Place them in a COMDAT group
+  // if the associated function is a COMDAT. This will make sure that
+  // only one copy of counters of the COMDAT function will be emitted after
+  // linking.
   Function *Fn = Inc->getParent()->getParent();
+  Comdat *ProfileVarsComdat = nullptr;
+  if (Fn->hasComdat())
+    ProfileVarsComdat = M->getOrInsertComdat(StringRef(getVarName(Inc, "vars")));
   Name->setSection(getNameSection());
   Name->setAlignment(1);
-  Name->setComdat(Fn->getComdat());
+  Name->setComdat(ProfileVarsComdat);
 
   uint64_t NumCounters = Inc->getNumCounters()->getZExtValue();
   LLVMContext &Ctx = M->getContext();
@@ -215,7 +219,7 @@
   Counters->setVisibility(Name->getVisibility());
   Counters->setSection(getCountersSection());
   Counters->setAlignment(8);
-  Counters->setComdat(Fn->getComdat());
+  Counters->setComdat(ProfileVarsComdat);
 
   RegionCounters[Inc->getName()] = Counters;
 
@@ -240,7 +244,7 @@
   Data->setVisibility(Name->getVisibility());
   Data->setSection(getDataSection());
   Data->setAlignment(8);
-  Data->setComdat(Fn->getComdat());
+  Data->setComdat(ProfileVarsComdat);
 
   // Mark the data variable as used so that it isn't stripped out.
   UsedVars.push_back(Data);
Index: test/Instrumentation/InstrProfiling/PR23499.ll
===================================================================
--- test/Instrumentation/InstrProfiling/PR23499.ll
+++ test/Instrumentation/InstrProfiling/PR23499.ll
@@ -8,9 +8,9 @@
 
 @__llvm_profile_name__Z3barIvEvv = linkonce_odr hidden constant [11 x i8] c"_Z3barIvEvv", align 1
 
-; CHECK: @__llvm_profile_name__Z3barIvEvv = linkonce_odr hidden constant [11 x i8] c"_Z3barIvEvv", section "{{.*}}__llvm_prf_names", comdat($_Z3barIvEvv), align 1
-; CHECK: @__llvm_profile_counters__Z3barIvEvv = linkonce_odr hidden global [1 x i64] zeroinitializer, section "{{.*}}__llvm_prf_cnts", comdat($_Z3barIvEvv), align 8
-; CHECK: @__llvm_profile_data__Z3barIvEvv = linkonce_odr hidden constant { i32, i32, i64, i8*, i64* } { i32 11, i32 1, i64 0, i8* getelementptr inbounds ([11 x i8], [11 x i8]* @__llvm_profile_name__Z3barIvEvv, i32 0, i32 0), i64* getelementptr inbounds ([1 x i64], [1 x i64]* @__llvm_profile_counters__Z3barIvEvv, i32 0, i32 0) }, section "{{.*}}__llvm_prf_data", comdat($_Z3barIvEvv), align 8
+; CHECK: @__llvm_profile_name__Z3barIvEvv = linkonce_odr hidden constant [11 x i8] c"_Z3barIvEvv", section "{{.*}}__llvm_prf_names", comdat($__llvm_profile_vars__Z3barIvEvv), align 1
+; CHECK: @__llvm_profile_counters__Z3barIvEvv = linkonce_odr hidden global [1 x i64] zeroinitializer, section "{{.*}}__llvm_prf_cnts", comdat($__llvm_profile_vars__Z3barIvEvv), align 8
+; CHECK: @__llvm_profile_data__Z3barIvEvv = linkonce_odr hidden constant { i32, i32, i64, i8*, i64* } { i32 11, i32 1, i64 0, i8* getelementptr inbounds ([11 x i8], [11 x i8]* @__llvm_profile_name__Z3barIvEvv, i32 0, i32 0), i64* getelementptr inbounds ([1 x i64], [1 x i64]* @__llvm_profile_counters__Z3barIvEvv, i32 0, i32 0) }, section "{{.*}}__llvm_prf_data", comdat($__llvm_profile_vars__Z3barIvEvv), align 8
 
 declare void @llvm.instrprof.increment(i8*, i64, i32, i32) #1