diff --git a/clang/lib/CodeGen/CGDeclCXX.cpp b/clang/lib/CodeGen/CGDeclCXX.cpp
index 553fedebfe56b..d22f9dc3b68cd 100644
--- a/clang/lib/CodeGen/CGDeclCXX.cpp
+++ b/clang/lib/CodeGen/CGDeclCXX.cpp
@@ -581,6 +581,16 @@ CodeGenModule::EmitCXXGlobalVarDeclInitFunc(const VarDecl *D,
       // llvm.used to prevent linker GC.
       addUsedGlobal(COMDATKey);
     }
+
+    // If we used a COMDAT key for the global ctor, the init function can be
+    // discarded if the global ctor entry is discarded.
+    // FIXME: Do we need to restrict this to ELF and Wasm?
+    llvm::Comdat *C = Addr->getComdat();
+    if (COMDATKey && C &&
+        (getTarget().getTriple().isOSBinFormatELF() ||
+         getTarget().getTriple().isOSBinFormatWasm())) {
+      Fn->setComdat(C);
+    }
   } else {
     I = DelayedCXXInitPosition.find(D); // Re-do lookup in case of re-hash.
     if (I == DelayedCXXInitPosition.end()) {
diff --git a/clang/lib/CodeGen/ItaniumCXXABI.cpp b/clang/lib/CodeGen/ItaniumCXXABI.cpp
index d3dc0e6212b8c..8ddc2f1885eb1 100644
--- a/clang/lib/CodeGen/ItaniumCXXABI.cpp
+++ b/clang/lib/CodeGen/ItaniumCXXABI.cpp
@@ -2445,11 +2445,6 @@ void ItaniumCXXABI::EmitGuardedInit(CodeGenFunction &CGF,
         (CGM.getTarget().getTriple().isOSBinFormatELF() ||
          CGM.getTarget().getTriple().isOSBinFormatWasm())) {
       guard->setComdat(C);
-      // An inline variable's guard function is run from the per-TU
-      // initialization function, not via a dedicated global ctor function, so
-      // we can't put it in a comdat.
-      if (!NonTemplateInline)
-        CGF.CurFn->setComdat(C);
     } else if (CGM.supportsCOMDAT() && guard->isWeakForLinker()) {
       guard->setComdat(CGM.getModule().getOrInsertComdat(guard->getName()));
     }
diff --git a/clang/test/CodeGenCXX/cxx11-thread-local-instantiated.cpp b/clang/test/CodeGenCXX/cxx11-thread-local-instantiated.cpp
new file mode 100644
index 0000000000000..3c78c7f7df902
--- /dev/null
+++ b/clang/test/CodeGenCXX/cxx11-thread-local-instantiated.cpp
@@ -0,0 +1,26 @@
+// RUN: %clang_cc1 -std=c++11 -emit-llvm %s -o - -triple x86_64-linux-gnu | FileCheck %s
+
+// PR48030
+
+template<typename T> struct TLS { static thread_local T *mData; };
+inline decltype(nullptr) non_constant_initializer() { return nullptr; }
+template<typename T> thread_local T *TLS<T>::mData = non_constant_initializer();
+struct S {};
+S *current() { return TLS<S>::mData; };
+
+// CHECK-DAG: @_ZN3TLSI1SE5mDataE = linkonce_odr thread_local global {{.*}}, comdat,
+// CHECK-DAG: @_ZGVN3TLSI1SE5mDataE = linkonce_odr thread_local global {{.*}}, comdat($_ZN3TLSI1SE5mDataE),
+// CHECK-DAG: @_ZTHN3TLSI1SE5mDataE = linkonce_odr alias {{.*}} @__cxx_global_var_init
+
+// CHECK-LABEL: define {{.*}} @_Z7currentv()
+// CHECK: call {{.*}} @_ZTWN3TLSI1SE5mDataE()
+
+// CHECK-LABEL: define weak_odr hidden {{.*}} @_ZTWN3TLSI1SE5mDataE() {{.*}} comdat {
+// CHECK: call void @_ZTHN3TLSI1SE5mDataE()
+// CHECK: ret {{.*}} @_ZN3TLSI1SE5mDataE
+
+// Unlike for a global, the global initialization function must not be in a
+// COMDAT with the variable, because it is referenced from the _ZTH function
+// which is outside that COMDAT.
+//
+// CHECK-NOT: define {{.*}} @__cxx_global_var_init{{.*}}comdat
diff --git a/clang/test/CodeGenCXX/cxx11-thread-local.cpp b/clang/test/CodeGenCXX/cxx11-thread-local.cpp
index f3146715b9214..e63762ee7bfa0 100644
--- a/clang/test/CodeGenCXX/cxx11-thread-local.cpp
+++ b/clang/test/CodeGenCXX/cxx11-thread-local.cpp
@@ -179,8 +179,7 @@ int f() {
 
 // LINUX_AIX: define internal void @[[VF_M_INIT]]()
 // DARWIN: define internal cxx_fast_tlscc void @[[VF_M_INIT]]()
-// LINUX-SAME: comdat($_ZN1VIfE1mE)
-// DARWIN-NOT: comdat
+// CHECK-NOT: comdat
 // CHECK: load i8, i8* bitcast (i64* @_ZGVN1VIfE1mE to i8*)
 // CHECK: %[[VF_M_INITIALIZED:.*]] = icmp eq i8 %{{.*}}, 0
 // CHECK: br i1 %[[VF_M_INITIALIZED]],
@@ -192,8 +191,7 @@ int f() {
 
 // LINUX_AIX: define internal void @[[XF_M_INIT]]()
 // DARWIN: define internal cxx_fast_tlscc void @[[XF_M_INIT]]()
-// LINUX-SAME: comdat($_ZN1XIfE1mE)
-// DARWIN-NOT: comdat
+// CHECK-NOT: comdat
 // CHECK: load i8, i8* bitcast (i64* @_ZGVN1XIfE1mE to i8*)
 // CHECK: %[[XF_M_INITIALIZED:.*]] = icmp eq i8 %{{.*}}, 0
 // CHECK: br i1 %[[XF_M_INITIALIZED]],
@@ -313,8 +311,7 @@ void set_anon_i() {
 
 // LINUX_AIX: define internal void @[[V_M_INIT]]()
 // DARWIN: define internal cxx_fast_tlscc void @[[V_M_INIT]]()
-// LINUX-SAME: comdat($_ZN1VIiE1mE)
-// DARWIN-NOT: comdat
+// CHECK-NOT: comdat
 // CHECK: load i8, i8* bitcast (i64* @_ZGVN1VIiE1mE to i8*)
 // CHECK: %[[V_M_INITIALIZED:.*]] = icmp eq i8 %{{.*}}, 0
 // CHECK: br i1 %[[V_M_INITIALIZED]],
@@ -326,8 +323,7 @@ void set_anon_i() {
 
 // LINUX_AIX: define internal void @[[X_M_INIT]]()
 // DARWIN: define internal cxx_fast_tlscc void @[[X_M_INIT]]()
-// LINUX-SAME: comdat($_ZN1XIiE1mE)
-// DARWIN-NOT: comdat
+// CHECK-NOT: comdat
 // CHECK: load i8, i8* bitcast (i64* @_ZGVN1XIiE1mE to i8*)
 // CHECK: %[[X_M_INITIALIZED:.*]] = icmp eq i8 %{{.*}}, 0
 // CHECK: br i1 %[[X_M_INITIALIZED]],
diff --git a/clang/test/CodeGenCXX/cxx1z-inline-variables.cpp b/clang/test/CodeGenCXX/cxx1z-inline-variables.cpp
index a616e95a2be55..896db4acc1318 100644
--- a/clang/test/CodeGenCXX/cxx1z-inline-variables.cpp
+++ b/clang/test/CodeGenCXX/cxx1z-inline-variables.cpp
@@ -90,9 +90,7 @@ const int &yib = Y<int>::b;
 // CHECK-LABEL: define {{.*}}global_var_init
 // CHECK: call i32 @_Z1fv
 
-// CHECK-LABEL: define {{.*}}global_var_init
-// CHECK-NOT: comdat
-// CHECK-SAME: {{$}}
+// CHECK-LABEL: define {{.*}}global_var_init{{.*}} comdat($b)
 // CHECK: load atomic {{.*}} acquire, align
 // CHECK: br
 // CHECK: __cxa_guard_acquire(i64* @_ZGV1b)
diff --git a/clang/test/OpenMP/threadprivate_codegen.cpp b/clang/test/OpenMP/threadprivate_codegen.cpp
index c07ffe1a28ccb..f1ccb80cb3ab4 100644
--- a/clang/test/OpenMP/threadprivate_codegen.cpp
+++ b/clang/test/OpenMP/threadprivate_codegen.cpp
@@ -3847,7 +3847,7 @@ int foobar() {
 //
 //
 // CHECK-TLS1-LABEL: define {{[^@]+}}@__cxx_global_var_init.3
-// CHECK-TLS1-SAME: () #[[ATTR0]] comdat($_ZN2STI2S4E2stE) {
+// CHECK-TLS1-SAME: () #[[ATTR0]] {
 // CHECK-TLS1-NEXT:  entry:
 // CHECK-TLS1-NEXT:    [[TMP0:%.*]] = load i8, i8* bitcast (i64* @_ZGVN2STI2S4E2stE to i8*), align 8
 // CHECK-TLS1-NEXT:    [[GUARD_UNINITIALIZED:%.*]] = icmp eq i8 [[TMP0]], 0
@@ -4373,7 +4373,7 @@ int foobar() {
 //
 //
 // CHECK-TLS2-LABEL: define {{[^@]+}}@__cxx_global_var_init.3
-// CHECK-TLS2-SAME: () #[[ATTR6]] comdat($_ZN2STI2S4E2stE) {
+// CHECK-TLS2-SAME: () #[[ATTR6]] {
 // CHECK-TLS2-NEXT:  entry:
 // CHECK-TLS2-NEXT:    [[TMP0:%.*]] = load i8, i8* bitcast (i64* @_ZGVN2STI2S4E2stE to i8*), align 8
 // CHECK-TLS2-NEXT:    [[GUARD_UNINITIALIZED:%.*]] = icmp eq i8 [[TMP0]], 0
@@ -4906,7 +4906,7 @@ int foobar() {
 //
 //
 // CHECK-TLS3-LABEL: define {{[^@]+}}@__cxx_global_var_init.3
-// CHECK-TLS3-SAME: () #[[ATTR0]] comdat($_ZN2STI2S4E2stE) !dbg [[DBG289:![0-9]+]] {
+// CHECK-TLS3-SAME: () #[[ATTR0]] !dbg [[DBG289:![0-9]+]] {
 // CHECK-TLS3-NEXT:  entry:
 // CHECK-TLS3-NEXT:    [[TMP0:%.*]] = load i8, i8* bitcast (i64* @_ZGVN2STI2S4E2stE to i8*), align 8, !dbg [[DBG290:![0-9]+]]
 // CHECK-TLS3-NEXT:    [[GUARD_UNINITIALIZED:%.*]] = icmp eq i8 [[TMP0]], 0, !dbg [[DBG290]]
@@ -5459,7 +5459,7 @@ int foobar() {
 //
 //
 // CHECK-TLS4-LABEL: define {{[^@]+}}@__cxx_global_var_init.3
-// CHECK-TLS4-SAME: () #[[ATTR7]] comdat($_ZN2STI2S4E2stE) !dbg [[DBG289:![0-9]+]] {
+// CHECK-TLS4-SAME: () #[[ATTR7]] !dbg [[DBG289:![0-9]+]] {
 // CHECK-TLS4-NEXT:  entry:
 // CHECK-TLS4-NEXT:    [[TMP0:%.*]] = load i8, i8* bitcast (i64* @_ZGVN2STI2S4E2stE to i8*), align 8, !dbg [[DBG290:![0-9]+]]
 // CHECK-TLS4-NEXT:    [[GUARD_UNINITIALIZED:%.*]] = icmp eq i8 [[TMP0]], 0, !dbg [[DBG290]]