diff --git a/lld/test/wasm/relocation-bad-tls.s b/lld/test/wasm/relocation-bad-tls.s
--- a/lld/test/wasm/relocation-bad-tls.s
+++ b/lld/test/wasm/relocation-bad-tls.s
@@ -6,6 +6,8 @@
   .functype _start () -> ()
   i32.const foo@TLSREL
   i32.const bar@TLSREL
+  i32.const baz@TLSREL
+  drop
   drop
   drop
   end_function
@@ -24,3 +26,4 @@
 
 # CHECK: relocation R_WASM_MEMORY_ADDR_TLS_SLEB cannot be used against `foo` in non-TLS section: .data
 # CHECK: relocation R_WASM_MEMORY_ADDR_TLS_SLEB cannot be used against `bar` in non-TLS section: .bss
+# CHECK: relocation R_WASM_MEMORY_ADDR_TLS_SLEB cannot be used against an undefined symbol `baz`
diff --git a/lld/wasm/Relocations.cpp b/lld/wasm/Relocations.cpp
--- a/lld/wasm/Relocations.cpp
+++ b/lld/wasm/Relocations.cpp
@@ -112,6 +112,11 @@
       break;
     case R_WASM_MEMORY_ADDR_TLS_SLEB:
     case R_WASM_MEMORY_ADDR_TLS_SLEB64:
+      if (!sym->isDefined()) {
+        error(toString(file) + ": relocation " + relocTypeToString(reloc.Type) +
+              " cannot be used against an undefined symbol `" + toString(*sym) +
+              "`");
+      }
       // In single-threaded builds TLS is lowered away and TLS data can be
       // merged with normal data and allowing TLS relocation in non-TLS
       // segments.
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyLowerEmscriptenEHSjLj.cpp b/llvm/lib/Target/WebAssembly/WebAssemblyLowerEmscriptenEHSjLj.cpp
--- a/llvm/lib/Target/WebAssembly/WebAssemblyLowerEmscriptenEHSjLj.cpp
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyLowerEmscriptenEHSjLj.cpp
@@ -422,7 +422,7 @@
   // shared-memory module, which we don't want to be responsible for.
   auto *Subtarget = TM.getSubtargetImpl();
   auto TLS = Subtarget->hasAtomics() && Subtarget->hasBulkMemory()
-                 ? GlobalValue::LocalExecTLSModel
+                 ? GlobalValue::GeneralDynamicTLSModel
                  : GlobalValue::NotThreadLocal;
   GV->setThreadLocalMode(TLS);
   return GV;
diff --git a/llvm/test/CodeGen/WebAssembly/lower-em-exceptions.ll b/llvm/test/CodeGen/WebAssembly/lower-em-exceptions.ll
--- a/llvm/test/CodeGen/WebAssembly/lower-em-exceptions.ll
+++ b/llvm/test/CodeGen/WebAssembly/lower-em-exceptions.ll
@@ -9,8 +9,8 @@
 @_ZTIc = external constant i8*
 ; NO-TLS-DAG: __THREW__ = external global [[PTR]]
 ; NO-TLS-DAG: __threwValue = external global i32
-; TLS-DAG: __THREW__ = external thread_local(localexec) global [[PTR]]
-; TLS-DAG: __threwValue = external thread_local(localexec) global i32
+; TLS-DAG: __THREW__ = external thread_local global [[PTR]]
+; TLS-DAG: __threwValue = external thread_local global i32
 
 ; Test invoke instruction with clauses (try-catch block)
 define void @clause() personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
diff --git a/llvm/test/CodeGen/WebAssembly/lower-em-sjlj.ll b/llvm/test/CodeGen/WebAssembly/lower-em-sjlj.ll
--- a/llvm/test/CodeGen/WebAssembly/lower-em-sjlj.ll
+++ b/llvm/test/CodeGen/WebAssembly/lower-em-sjlj.ll
@@ -10,8 +10,8 @@
 @global_var = global i32 0, align 4
 ; NO-TLS-DAG: __THREW__ = external global [[PTR]]
 ; NO-TLS-DAG: __threwValue = external global [[PTR]]
-; TLS-DAG: __THREW__ = external thread_local(localexec) global i32
-; TLS-DAG: __threwValue = external thread_local(localexec) global i32
+; TLS-DAG: __THREW__ = external thread_local global i32
+; TLS-DAG: __threwValue = external thread_local global i32
 @global_longjmp_ptr = global void (%struct.__jmp_buf_tag*, i32)* @longjmp, align 4
 ; CHECK-DAG: @global_longjmp_ptr = global void (%struct.__jmp_buf_tag*, i32)* bitcast (void ([[PTR]], i32)* @emscripten_longjmp to void (%struct.__jmp_buf_tag*, i32)*)