diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -15326,6 +15326,15 @@
       return true;
     }
 
+    if (getLangOpts().OpenMP && getLangOpts().OpenMPUseTLS) {
+      // Avoid capturing TLS-backed threadprivate variables in outer scopes.
+      if (VarDC->Equals(ParentDC) && Var->hasAttr<OMPThreadPrivateDeclAttr>() &&
+          IsGlobal) {
+        FunctionScopesIndex = MaxFunctionScopesIndex - 1;
+        break;
+      }
+    }
+
     FunctionScopeInfo  *FSI = FunctionScopes[FunctionScopesIndex];
     CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FSI);
 
diff --git a/clang/test/OpenMP/nested_parallel_threadprivate_copyin.cpp b/clang/test/OpenMP/nested_parallel_threadprivate_copyin.cpp
new file mode 100644
--- /dev/null
+++ b/clang/test/OpenMP/nested_parallel_threadprivate_copyin.cpp
@@ -0,0 +1,48 @@
+// RUN: %clang_cc1 %s -fopenmp -emit-llvm -o - | FileCheck %s
+#define NT 4                   /* default number of threads */
+
+extern "C" {
+extern int printf(const char *, ...);
+extern void assert(int);
+extern void omp_set_dynamic(bool);
+extern void omp_set_num_threads(int);
+extern void omp_set_nested(bool);
+extern int omp_get_thread_num(void);
+extern int omp_get_ancestor_thread_num(int);
+};
+
+int main(void) {
+    static int threadprivate_var = 1;
+    #pragma omp threadprivate(threadprivate_var)
+
+    // These commands are not strictly necessary, but they make it easier to
+    // see when things go wrong.
+    omp_set_dynamic(false);
+    omp_set_num_threads(NT);
+    omp_set_nested(true);
+
+    // CHECK-NOT: call void.*@__kmpc_fork_call({{.*}}%{{\w+}}threadprivate{{.*}})
+    // CHECK-NOT: define internal void @.omp_outlined.({{.*}}%threadprivate_var{{.*}})
+    #pragma omp parallel
+    {
+        threadprivate_var = 1;
+        printf("[B] thread %d: val %d: threadprivate @ %p\n", omp_get_thread_num(), threadprivate_var, &threadprivate_var);
+
+        #pragma omp master
+        {
+            threadprivate_var = 2;
+            // CHECK: define internal void @.omp_outlined..2({{.*}}%threadprivate_var{{.*}})
+            #pragma omp parallel copyin(threadprivate_var)
+            {
+                printf("[B] thread %d, %d: val %d: threadprivate @ %p\n", omp_get_ancestor_thread_num(1), omp_get_thread_num(), threadprivate_var, &threadprivate_var);
+                // check that copyin succeeded
+                assert(threadprivate_var == 2);
+            }
+        }
+        #pragma omp barrier
+        printf("[A] thread %d: val %d: threadprivate @ %p\n", omp_get_thread_num(), threadprivate_var, &threadprivate_var);
+        if (omp_get_thread_num() != 0)  // 0 is the master thread
+            // non-master threads should not have seen changes
+            assert(threadprivate_var == 1);
+    }
+}