diff --git a/compiler-rt/test/profile/coverage-weak.cpp b/compiler-rt/test/profile/coverage-weak.cpp
new file mode 100644
--- /dev/null
+++ b/compiler-rt/test/profile/coverage-weak.cpp
@@ -0,0 +1,46 @@
+/// Test instrumentation can handle non-comdat weak functions.
+// RUN: %clang_profgen -g -fcoverage-mapping -c -o %t1.o %s
+// RUN: %clang_profgen -g -fcoverage-mapping -c -o %t2.o %s -DOBJECT_2
+// RUN: %clang_profgen -g -fcoverage-mapping %t1.o %t2.o -o %t.exe
+// RUN: env LLVM_PROFILE_FILE=%t.profraw %run %t.exe
+// RUN: llvm-profdata show %t.profraw --all-functions | FileCheck %s
+
+/// Additionally test associative comdat on Windows.
+// RUN: %clang_profgen -g -fcoverage-mapping -c -o %t1.o %s -ffunction-sections
+// RUN: %clang_profgen -g -fcoverage-mapping -c -o %t2.o %s -ffunction-sections -DOBJECT_2
+// RUN: %clang_profgen -g -fcoverage-mapping %t1.o %t2.o -o %t.exe
+// RUN: env LLVM_PROFILE_FILE=%t.profraw %run %t.exe
+// RUN: llvm-profdata show %t.profraw --all-functions | FileCheck %s
+
+// CHECK:      main:
+// CHECK-NEXT:    Hash:
+// CHECK-NEXT:    Counters: 1
+// CHECK-NEXT:    Function count: 1
+// CHECK:      {{.*}}weak{{.*}}:
+// CHECK-NEXT:    Hash:
+// CHECK-NEXT:    Counters: 1
+// CHECK-NEXT:    Function count: 2
+// CHECK:      {{.*}}foo{{.*}}:
+// CHECK-NEXT:    Hash:
+// CHECK-NEXT:    Counters: 1
+// CHECK-NEXT:    Function count: 1
+
+#ifdef OBJECT_2
+extern "C" int puts(const char *);
+
+__attribute__((weak)) void weak(const char *msg) {
+  puts(msg);
+}
+
+void foo() {
+  weak("shared");
+}
+#else
+void weak(const char *msg);
+void foo();
+
+int main() {
+  weak("main");
+  foo();
+}
+#endif
diff --git a/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp b/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
--- a/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
+++ b/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
@@ -821,15 +821,10 @@
     PD = It->second;
   }
 
-  // Match the linkage and visibility of the name global. COFF supports using
-  // comdats with internal symbols, so do that if we can.
+  // Match the linkage and visibility of the name global.
   Function *Fn = Inc->getParent()->getParent();
   GlobalValue::LinkageTypes Linkage = NamePtr->getLinkage();
   GlobalValue::VisibilityTypes Visibility = NamePtr->getVisibility();
-  if (TT.isOSBinFormatCOFF()) {
-    Linkage = GlobalValue::InternalLinkage;
-    Visibility = GlobalValue::DefaultVisibility;
-  }
 
   // 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
@@ -838,23 +833,19 @@
   // new comdat group for the counters and profiling data. If we use the comdat
   // of the parent function, that will result in relocations against discarded
   // sections.
+  //
+  // For COFF, put the counters, data, and values each into their own
+  // comdats. We can't use a group because the Visual C++ linker will
+  // report duplicate symbol errors if there are multiple external symbols
+  // with the same name marked IMAGE_COMDAT_SELECT_ASSOCIATIVE.
+  //
+  // For ELF, when not using COMDAT, put counters, data and values into a
+  // noduplicates COMDAT which is lowered to a zero-flag section group. This
+  // allows -z start-stop-gc to discard the entire group when the function is
+  // discarded.
   bool NeedComdat = needsComdatForCounter(*Fn, *M);
-  if (NeedComdat) {
-    if (TT.isOSBinFormatCOFF()) {
-      // For COFF, put the counters, data, and values each into their own
-      // comdats. We can't use a group because the Visual C++ linker will
-      // report duplicate symbol errors if there are multiple external symbols
-      // with the same name marked IMAGE_COMDAT_SELECT_ASSOCIATIVE.
-      Linkage = GlobalValue::LinkOnceODRLinkage;
-      Visibility = GlobalValue::HiddenVisibility;
-    }
-  }
   std::string DataVarName = getVarName(Inc, getInstrProfDataVarPrefix());
   auto MaybeSetComdat = [=](GlobalVariable *GV) {
-    // For ELF, when not using COMDAT, put counters, data and values into
-    // a noduplicates COMDAT which is lowered to a zero-flag section group.
-    // This allows linker GC to discard the entire group when the function
-    // is discarded.
     bool UseComdat = (NeedComdat || TT.isOSBinFormatELF());
     if (UseComdat) {
       auto GroupName = TT.isOSBinFormatCOFF() ? GV->getName() : DataVarName;
diff --git a/llvm/test/Instrumentation/InstrProfiling/linkage.ll b/llvm/test/Instrumentation/InstrProfiling/linkage.ll
--- a/llvm/test/Instrumentation/InstrProfiling/linkage.ll
+++ b/llvm/test/Instrumentation/InstrProfiling/linkage.ll
@@ -28,9 +28,9 @@
 ; ELF: @__profd_foo = private global {{.*}} section "__llvm_prf_data", comdat, align 8
 ; MACHO: @__profc_foo = private global
 ; MACHO: @__profd_foo = private global
-; COFF: @__profc_foo = internal global
+; COFF: @__profc_foo = private global
 ; COFF-NOT: comdat
-; COFF: @__profd_foo = internal global
+; COFF: @__profd_foo = private global
 define void @foo() {
   call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__profn_foo, i32 0, i32 0), i64 0, i32 1, i32 0)
   ret void
@@ -40,8 +40,8 @@
 ; ELF: @__profd_foo_weak = weak hidden global {{.*}} section "__llvm_prf_data", comdat, align 8
 ; MACHO: @__profc_foo_weak = weak hidden global
 ; MACHO: @__profd_foo_weak = weak hidden global
-; COFF: @__profc_foo_weak = internal global
-; COFF: @__profd_foo_weak = internal global
+; COFF: @__profc_foo_weak = weak hidden global
+; COFF: @__profd_foo_weak = weak hidden global
 define weak void @foo_weak() {
   call void @llvm.instrprof.increment(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @__profn_foo_weak, i32 0, i32 0), i64 0, i32 1, i32 0)
   ret void
@@ -51,8 +51,8 @@
 ; ELF: @"__profd_linkage.ll:foo_internal" = private global {{.*}} section "__llvm_prf_data", comdat, align 8
 ; MACHO: @"__profc_linkage.ll:foo_internal" = private global
 ; MACHO: @"__profd_linkage.ll:foo_internal" = private global
-; COFF: @"__profc_linkage.ll:foo_internal" = internal global
-; COFF: @"__profd_linkage.ll:foo_internal" = internal global
+; COFF: @"__profc_linkage.ll:foo_internal" = private global
+; COFF: @"__profd_linkage.ll:foo_internal" = private global
 define internal void @foo_internal() {
   call void @llvm.instrprof.increment(i8* getelementptr inbounds ([23 x i8], [23 x i8]* @"__profn_linkage.ll:foo_internal", i32 0, i32 0), i64 0, i32 1, i32 0)
   ret void
@@ -62,8 +62,8 @@
 ; ELF: @__profd_foo_inline = linkonce_odr hidden global {{.*}} section "__llvm_prf_data", comdat, align 8
 ; MACHO: @__profc_foo_inline = linkonce_odr hidden global
 ; MACHO: @__profd_foo_inline = linkonce_odr hidden global
-; COFF: @__profc_foo_inline = internal global{{.*}} section ".lprfc$M", align 8
-; COFF: @__profd_foo_inline = internal global{{.*}} section ".lprfd$M", align 8
+; COFF: @__profc_foo_inline = linkonce_odr hidden global{{.*}} section ".lprfc$M", align 8
+; COFF: @__profd_foo_inline = linkonce_odr hidden global{{.*}} section ".lprfd$M", align 8
 define linkonce_odr void @foo_inline() {
   call void @llvm.instrprof.increment(i8* getelementptr inbounds ([10 x i8], [10 x i8]* @__profn_foo_inline, i32 0, i32 0), i64 0, i32 1, i32 0)
   ret void
diff --git a/llvm/test/Instrumentation/InstrProfiling/platform.ll b/llvm/test/Instrumentation/InstrProfiling/platform.ll
--- a/llvm/test/Instrumentation/InstrProfiling/platform.ll
+++ b/llvm/test/Instrumentation/InstrProfiling/platform.ll
@@ -20,11 +20,11 @@
 
 ; MACHO: @__profc_foo = private global [1 x i64] zeroinitializer, section "__DATA,__llvm_prf_cnts", align 8
 ; ELF: @__profc_foo = private global [1 x i64] zeroinitializer, section "__llvm_prf_cnts", comdat($__profd_foo), align 8
-; WINDOWS: @__profc_foo = internal global [1 x i64] zeroinitializer, section ".lprfc$M", align 8
+; WINDOWS: @__profc_foo = private global [1 x i64] zeroinitializer, section ".lprfc$M", align 8
 
 ; MACHO: @__profd_foo = private {{.*}}, section "__DATA,__llvm_prf_data,regular,live_support", align 8
 ; ELF: @__profd_foo = private {{.*}}, section "__llvm_prf_data", comdat, align 8
-; WINDOWS: @__profd_foo = internal global {{.*}}, section ".lprfd$M", align 8
+; WINDOWS: @__profd_foo = private global {{.*}}, section ".lprfd$M", align 8
 
 ; ELF: @__llvm_prf_nm = private constant [{{.*}} x i8] c"{{.*}}", section "{{.*}}__llvm_prf_names", align 1
 ; WINDOWS: @__llvm_prf_nm = private constant [{{.*}} x i8] c"{{.*}}", section "{{.*}}lprfn$M", align 1
diff --git a/llvm/test/Instrumentation/InstrProfiling/profiling.ll b/llvm/test/Instrumentation/InstrProfiling/profiling.ll
--- a/llvm/test/Instrumentation/InstrProfiling/profiling.ll
+++ b/llvm/test/Instrumentation/InstrProfiling/profiling.ll
@@ -21,8 +21,8 @@
 ; ELF:   @__profd_foo = private {{.*}}, section "__llvm_prf_data", comdat, align 8
 ; MACHO: @__profc_foo = private global [1 x i64] zeroinitializer, section "__DATA,__llvm_prf_cnts", align 8
 ; MACHO: @__profd_foo = private {{.*}}, section "__DATA,__llvm_prf_data,regular,live_support", align 8
-; WIN:   @__profc_foo = internal global [1 x i64] zeroinitializer, section ".lprfc$M", align 8
-; WIN:   @__profd_foo = internal {{.*}}, section ".lprfd$M", align 8
+; WIN:   @__profc_foo = private global [1 x i64] zeroinitializer, section ".lprfc$M", align 8
+; WIN:   @__profd_foo = private {{.*}}, section ".lprfd$M", align 8
 define void @foo() {
   call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__profn_foo, i32 0, i32 0), i64 0, i32 1, i32 0)
   ret void
@@ -32,8 +32,8 @@
 ; ELF:   @__profd_bar = private {{.*}}, section "__llvm_prf_data", comdat, align 8
 ; MACHO: @__profc_bar = private global [1 x i64] zeroinitializer, section "__DATA,__llvm_prf_cnts", align 8
 ; MACHO: @__profd_bar = private {{.*}}, section "__DATA,__llvm_prf_data,regular,live_support", align 8
-; WIN:   @__profc_bar = internal global [1 x i64] zeroinitializer, section ".lprfc$M", align 8
-; WIN:   @__profd_bar = internal {{.*}}, section ".lprfd$M", align 8
+; WIN:   @__profc_bar = private global [1 x i64] zeroinitializer, section ".lprfc$M", align 8
+; WIN:   @__profd_bar = private {{.*}}, section ".lprfd$M", align 8
 define void @bar() {
   call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__profn_bar, i32 0, i32 0), i64 0, i32 1, i32 0)
   ret void
@@ -43,8 +43,8 @@
 ; ELF:   @__profd_baz = private {{.*}}, section "__llvm_prf_data", comdat, align 8
 ; MACHO: @__profc_baz = private global [3 x i64] zeroinitializer, section "__DATA,__llvm_prf_cnts", align 8
 ; MACHO: @__profd_baz = private {{.*}}, section "__DATA,__llvm_prf_data,regular,live_support", align 8
-; WIN:   @__profc_baz = internal global [3 x i64] zeroinitializer, section ".lprfc$M", align 8
-; WIN:   @__profd_baz = internal {{.*}}, section ".lprfd$M", align 8
+; WIN:   @__profc_baz = private global [3 x i64] zeroinitializer, section ".lprfc$M", align 8
+; WIN:   @__profd_baz = private {{.*}}, section ".lprfd$M", align 8
 define void @baz() {
   call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__profn_baz, i32 0, i32 0), i64 0, i32 3, i32 0)
   call void @llvm.instrprof.increment(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @__profn_baz, i32 0, i32 0), i64 0, i32 3, i32 1)