Index: lib/Sema/SemaOpenMP.cpp
===================================================================
--- lib/Sema/SemaOpenMP.cpp
+++ lib/Sema/SemaOpenMP.cpp
@@ -11531,20 +11531,12 @@
   }
   Type = Type.getNonReferenceType();
 
-  // A list item must not be const-qualified.
-  if (Type.isConstant(Context)) {
-    Diag(ELoc, diag::err_omp_const_variable)
-        << getOpenMPClauseName(OMPC_linear);
-    if (D) {
-      bool IsDecl =
-          !VD ||
-          VD->isThisDeclarationADefinition(Context) == VarDecl::DeclarationOnly;
-      Diag(D->getLocation(),
-           IsDecl ? diag::note_previous_decl : diag::note_defined_here)
-          << D;
-    }
+  // OpenMP 5.0 [2.19.3, List Item Privatization, Restrictions]
+  // A variable that is privatized must not have a const-qualified type
+  // unless it is of class type with a mutable member. This restriction does
+  // not apply to the firstprivate clause.
+  if (rejectConstNotMutableType(*this, D, Type, OMPC_linear, ELoc))
     return true;
-  }
 
   // A list item must be of integral or pointer type.
   Type = Type.getUnqualifiedType().getCanonicalType();
Index: test/OpenMP/distribute_parallel_for_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/distribute_parallel_for_simd_linear_messages.cpp
+++ test/OpenMP/distribute_parallel_for_simd_linear_messages.cpp
@@ -189,7 +189,7 @@
 
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp distribute parallel for simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
@@ -294,7 +294,7 @@
 
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute parallel for simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}} expected-error {{incomplete type 'S1' where a complete type is required}}
+#pragma omp distribute parallel for simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}} expected-error {{incomplete type 'S1' where a complete type is required}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
Index: test/OpenMP/distribute_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/distribute_simd_linear_messages.cpp
+++ test/OpenMP/distribute_simd_linear_messages.cpp
@@ -189,7 +189,7 @@
 
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp distribute simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
@@ -283,7 +283,7 @@
 
 #pragma omp target
 #pragma omp teams
-#pragma omp distribute simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}} expected-warning {{Non-trivial type 'const S2' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-error {{incomplete type 'S1' where a complete type is required}}
+#pragma omp distribute simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}} expected-warning {{Non-trivial type 'const S2' is mapped, only trivial types are guaranteed to be mapped correctly}} expected-error {{incomplete type 'S1' where a complete type is required}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
Index: test/OpenMP/for_linear_messages.cpp
===================================================================
--- test/OpenMP/for_linear_messages.cpp
+++ test/OpenMP/for_linear_messages.cpp
@@ -122,7 +122,7 @@
   #pragma omp for linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp for linear (a, b:B::ib)
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp for linear (argv[1]) // expected-error {{expected variable name}}
@@ -188,7 +188,7 @@
   #pragma omp for linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp for linear(a, b)
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp for linear (argv[1]) // expected-error {{expected variable name}}
Index: test/OpenMP/for_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/for_simd_linear_messages.cpp
+++ test/OpenMP/for_simd_linear_messages.cpp
@@ -122,7 +122,7 @@
   #pragma omp for simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp for simd linear (a, b:B::ib)
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp for simd linear (argv[1]) // expected-error {{expected variable name}}
@@ -186,7 +186,7 @@
   #pragma omp for simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp for simd linear (a, b) 
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp for simd linear (argv[1]) // expected-error {{expected variable name}}
Index: test/OpenMP/parallel_for_linear_messages.cpp
===================================================================
--- test/OpenMP/parallel_for_linear_messages.cpp
+++ test/OpenMP/parallel_for_linear_messages.cpp
@@ -146,7 +146,7 @@
   for (int k = 0; k < argc; ++k)
     ++k;
 // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-// expected-error@+1 {{const-qualified variable cannot be linear}}
+// expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
 #pragma omp parallel for linear(a, b : B::ib)
   for (int k = 0; k < argc; ++k)
     ++k;
@@ -231,7 +231,7 @@
   for (int k = 0; k < argc; ++k)
     ++k;
 // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-// expected-error@+1 {{const-qualified variable cannot be linear}}
+// expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
 #pragma omp parallel for linear(a, b)
   for (int k = 0; k < argc; ++k)
     ++k;
Index: test/OpenMP/parallel_for_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/parallel_for_simd_linear_messages.cpp
+++ test/OpenMP/parallel_for_simd_linear_messages.cpp
@@ -122,7 +122,7 @@
   #pragma omp parallel for simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp parallel for simd linear (a, b:B::ib)
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp parallel for simd linear (argv[1]) // expected-error {{expected variable name}}
@@ -186,7 +186,7 @@
   #pragma omp parallel for simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp parallel for simd linear (a, b) 
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp parallel for simd linear (argv[1]) // expected-error {{expected variable name}}
Index: test/OpenMP/simd_linear_messages.cpp
===================================================================
--- test/OpenMP/simd_linear_messages.cpp
+++ test/OpenMP/simd_linear_messages.cpp
@@ -132,7 +132,7 @@
   #pragma omp simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp simd linear (val(a, b):B::ib)
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp simd linear (argv[1]) // expected-error {{expected variable name}}
@@ -221,7 +221,7 @@
   #pragma omp simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp simd linear(a, b)
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp simd linear (argv[1]) // expected-error {{expected variable name}}
Index: test/OpenMP/target_parallel_for_linear_messages.cpp
===================================================================
--- test/OpenMP/target_parallel_for_linear_messages.cpp
+++ test/OpenMP/target_parallel_for_linear_messages.cpp
@@ -146,7 +146,7 @@
   for (int k = 0; k < argc; ++k)
     ++k;
 // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-// expected-error@+1 {{const-qualified variable cannot be linear}}
+// expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
 #pragma omp target parallel for linear(a, b : B::ib)
   for (int k = 0; k < argc; ++k)
     ++k;
@@ -231,7 +231,7 @@
   for (int k = 0; k < argc; ++k)
     ++k;
 // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-// expected-error@+1 {{const-qualified variable cannot be linear}}
+// expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
 #pragma omp target parallel for linear(a, b)
   for (int k = 0; k < argc; ++k)
     ++k;
Index: test/OpenMP/target_parallel_for_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/target_parallel_for_simd_linear_messages.cpp
+++ test/OpenMP/target_parallel_for_simd_linear_messages.cpp
@@ -146,7 +146,7 @@
   for (int k = 0; k < argc; ++k)
     ++k;
 // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-// expected-error@+1 {{const-qualified variable cannot be linear}}
+// expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
 #pragma omp target parallel for simd linear(a, b : B::ib)
   for (int k = 0; k < argc; ++k)
     ++k;
@@ -231,7 +231,7 @@
   for (int k = 0; k < argc; ++k)
     ++k;
 // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-// expected-error@+1 {{const-qualified variable cannot be linear}}
+// expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
 #pragma omp target parallel for simd linear(a, b)
   for (int k = 0; k < argc; ++k)
     ++k;
Index: test/OpenMP/target_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/target_simd_linear_messages.cpp
+++ test/OpenMP/target_simd_linear_messages.cpp
@@ -146,7 +146,7 @@
   for (int k = 0; k < argc; ++k)
     ++k;
 // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-// expected-error@+1 {{const-qualified variable cannot be linear}}
+// expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
 #pragma omp target simd linear(a, b : B::ib)
   for (int k = 0; k < argc; ++k)
     ++k;
@@ -231,7 +231,7 @@
   for (int k = 0; k < argc; ++k)
     ++k;
 // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-// expected-error@+1 {{const-qualified variable cannot be linear}}
+// expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
 #pragma omp target simd linear(a, b)
   for (int k = 0; k < argc; ++k)
     ++k;
Index: test/OpenMP/target_teams_distribute_parallel_for_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/target_teams_distribute_parallel_for_simd_linear_messages.cpp
+++ test/OpenMP/target_teams_distribute_parallel_for_simd_linear_messages.cpp
@@ -148,7 +148,7 @@
 #pragma omp target teams distribute parallel for simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
 
-#pragma omp target teams distribute parallel for simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp target teams distribute parallel for simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target teams distribute parallel for simd linear (argv[1]) // expected-error {{expected variable name}}
@@ -216,7 +216,7 @@
   for (int k = 0; k < argc; ++k) ++k;
 
 
-#pragma omp target teams distribute parallel for simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp target teams distribute parallel for simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target teams distribute parallel for simd linear (argv[1]) // expected-error {{expected variable name}}
Index: test/OpenMP/target_teams_distribute_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/target_teams_distribute_simd_linear_messages.cpp
+++ test/OpenMP/target_teams_distribute_simd_linear_messages.cpp
@@ -148,7 +148,7 @@
 #pragma omp target teams distribute simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
 
-#pragma omp target teams distribute simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp target teams distribute simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target teams distribute simd linear (argv[1]) // expected-error {{expected variable name}}
@@ -216,7 +216,7 @@
   for (int k = 0; k < argc; ++k) ++k;
 
 
-#pragma omp target teams distribute simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp target teams distribute simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target teams distribute simd linear (argv[1]) // expected-error {{expected variable name}}
Index: test/OpenMP/taskloop_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/taskloop_simd_linear_messages.cpp
+++ test/OpenMP/taskloop_simd_linear_messages.cpp
@@ -132,7 +132,7 @@
   #pragma omp taskloop simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp taskloop simd linear (val(a, b):B::ib)
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp taskloop simd linear (argv[1]) // expected-error {{expected variable name}}
@@ -221,7 +221,7 @@
   #pragma omp taskloop simd linear (S1) // expected-error {{'S1' does not refer to a value}}
   for (int k = 0; k < argc; ++k) ++k;
   // expected-error@+2 {{linear variable with incomplete type 'S1'}}
-  // expected-error@+1 {{const-qualified variable cannot be linear}}
+  // expected-error@+1 {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   #pragma omp taskloop simd linear(a, b)
   for (int k = 0; k < argc; ++k) ++k;
   #pragma omp taskloop simd linear (argv[1]) // expected-error {{expected variable name}}
Index: test/OpenMP/teams_distribute_parallel_for_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/teams_distribute_parallel_for_simd_linear_messages.cpp
+++ test/OpenMP/teams_distribute_parallel_for_simd_linear_messages.cpp
@@ -169,7 +169,7 @@
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
-#pragma omp teams distribute parallel for simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp teams distribute parallel for simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
@@ -250,7 +250,7 @@
 
 
 #pragma omp target
-#pragma omp teams distribute parallel for simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp teams distribute parallel for simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
Index: test/OpenMP/teams_distribute_simd_linear_messages.cpp
===================================================================
--- test/OpenMP/teams_distribute_simd_linear_messages.cpp
+++ test/OpenMP/teams_distribute_simd_linear_messages.cpp
@@ -169,7 +169,7 @@
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
-#pragma omp teams distribute simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp teams distribute simd linear (a, b:B::ib) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target
@@ -250,7 +250,7 @@
 
 
 #pragma omp target
-#pragma omp teams distribute simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{const-qualified variable cannot be linear}}
+#pragma omp teams distribute simd linear (a, b) // expected-error {{linear variable with incomplete type 'S1'}} expected-error {{argument of a linear clause should be of integral or pointer type, not 'S2'}}
   for (int k = 0; k < argc; ++k) ++k;
 
 #pragma omp target