diff --git a/flang/include/flang/Parser/parse-tree.h b/flang/include/flang/Parser/parse-tree.h
index 10d7840775e88..8f50809599a58 100644
--- a/flang/include/flang/Parser/parse-tree.h
+++ b/flang/include/flang/Parser/parse-tree.h
@@ -3544,7 +3544,7 @@ struct OmpDefaultmapClause {
   TUPLE_CLASS_BOILERPLATE(OmpDefaultmapClause);
   ENUM_CLASS(
       ImplicitBehavior, Alloc, To, From, Tofrom, Firstprivate, None, Default)
-  ENUM_CLASS(VariableCategory, Scalar, Aggregate, Allocatable, Pointer)
+  ENUM_CLASS(VariableCategory, All, Scalar, Aggregate, Allocatable, Pointer)
   std::tuple<ImplicitBehavior, std::optional<VariableCategory>> t;
 };
 
diff --git a/flang/lib/Lower/OpenMP/Clauses.cpp b/flang/lib/Lower/OpenMP/Clauses.cpp
index 3dedd4864bafc..5879fbe619312 100644
--- a/flang/lib/Lower/OpenMP/Clauses.cpp
+++ b/flang/lib/Lower/OpenMP/Clauses.cpp
@@ -561,17 +561,20 @@ Defaultmap make(const parser::OmpClause::Defaultmap &inp,
   CLAUSET_ENUM_CONVERT( //
       convert2, wrapped::VariableCategory, Defaultmap::VariableCategory,
       // clang-format off
-      MS(Scalar,       Scalar)
       MS(Aggregate,    Aggregate)
-      MS(Pointer,      Pointer)
+      MS(All,          All)
       MS(Allocatable,  Allocatable)
+      MS(Pointer,      Pointer)
+      MS(Scalar,       Scalar)
       // clang-format on
   );
 
   auto &t0 = std::get<wrapped::ImplicitBehavior>(inp.v.t);
   auto &t1 = std::get<std::optional<wrapped::VariableCategory>>(inp.v.t);
+
+  auto category = t1 ? convert2(*t1) : Defaultmap::VariableCategory::All;
   return Defaultmap{{/*ImplicitBehavior=*/convert1(t0),
-                     /*VariableCategory=*/maybeApply(convert2, t1)}};
+                     /*VariableCategory=*/category}};
 }
 
 Doacross makeDoacross(const parser::OmpDoacross &doa,
diff --git a/flang/lib/Lower/OpenMP/OpenMP.cpp b/flang/lib/Lower/OpenMP/OpenMP.cpp
index 970e0db35c76f..e445bb10a3456 100644
--- a/flang/lib/Lower/OpenMP/OpenMP.cpp
+++ b/flang/lib/Lower/OpenMP/OpenMP.cpp
@@ -30,6 +30,7 @@
 #include "flang/Optimizer/Builder/Todo.h"
 #include "flang/Optimizer/Dialect/FIRType.h"
 #include "flang/Optimizer/HLFIR/HLFIROps.h"
+#include "flang/Parser/characters.h"
 #include "flang/Parser/parse-tree.h"
 #include "flang/Semantics/openmp-directive-sets.h"
 #include "flang/Semantics/tools.h"
@@ -2881,7 +2882,9 @@ static void genOMP(lower::AbstractConverter &converter, lower::SymMap &symTable,
         !std::holds_alternative<clause::InReduction>(clause.u) &&
         !std::holds_alternative<clause::Mergeable>(clause.u) &&
         !std::holds_alternative<clause::TaskReduction>(clause.u)) {
-      TODO(clauseLocation, "OpenMP Block construct clause");
+      std::string name =
+          parser::ToUpperCaseLetters(llvm::omp::getOpenMPClauseName(clause.id));
+      TODO(clauseLocation, name + " clause is not implemented yet");
     }
   }
 
diff --git a/flang/lib/Parser/openmp-parsers.cpp b/flang/lib/Parser/openmp-parsers.cpp
index 0c6bb54e48840..5ead9a48fa896 100644
--- a/flang/lib/Parser/openmp-parsers.cpp
+++ b/flang/lib/Parser/openmp-parsers.cpp
@@ -270,7 +270,7 @@ TYPE_PARSER(construct<OmpMapClause>(
 // 2.19.7.2 defaultmap(implicit-behavior[:variable-category])
 //  implicit-behavior -> ALLOC | TO | FROM | TOFROM | FIRSRTPRIVATE | NONE |
 //  DEFAULT
-//  variable-category -> SCALAR | AGGREGATE | ALLOCATABLE | POINTER
+//  variable-category -> ALL | SCALAR | AGGREGATE | ALLOCATABLE | POINTER
 TYPE_PARSER(construct<OmpDefaultmapClause>(
     construct<OmpDefaultmapClause::ImplicitBehavior>(
         "ALLOC" >> pure(OmpDefaultmapClause::ImplicitBehavior::Alloc) ||
@@ -283,6 +283,7 @@ TYPE_PARSER(construct<OmpDefaultmapClause>(
         "DEFAULT" >> pure(OmpDefaultmapClause::ImplicitBehavior::Default)),
     maybe(":" >>
         construct<OmpDefaultmapClause::VariableCategory>(
+            "ALL"_id >> pure(OmpDefaultmapClause::VariableCategory::All) ||
             "SCALAR" >> pure(OmpDefaultmapClause::VariableCategory::Scalar) ||
             "AGGREGATE" >>
                 pure(OmpDefaultmapClause::VariableCategory::Aggregate) ||
diff --git a/flang/lib/Semantics/check-omp-structure.cpp b/flang/lib/Semantics/check-omp-structure.cpp
index 3b03eab943422..0b64a4a9801cc 100644
--- a/flang/lib/Semantics/check-omp-structure.cpp
+++ b/flang/lib/Semantics/check-omp-structure.cpp
@@ -3333,14 +3333,17 @@ void OmpStructureChecker::Leave(const parser::OmpAtomicRead &) {
   CheckNotAllowedIfClause(llvm::omp::Clause::OMPC_read,
       {llvm::omp::Clause::OMPC_release, llvm::omp::Clause::OMPC_acq_rel});
 }
+
 void OmpStructureChecker::Leave(const parser::OmpAtomicWrite &) {
   CheckNotAllowedIfClause(llvm::omp::Clause::OMPC_write,
       {llvm::omp::Clause::OMPC_acquire, llvm::omp::Clause::OMPC_acq_rel});
 }
+
 void OmpStructureChecker::Leave(const parser::OmpAtomicUpdate &) {
   CheckNotAllowedIfClause(llvm::omp::Clause::OMPC_update,
       {llvm::omp::Clause::OMPC_acquire, llvm::omp::Clause::OMPC_acq_rel});
 }
+
 // OmpAtomic node represents atomic directive without atomic-clause.
 // atomic-clause - READ,WRITE,UPDATE,CAPTURE.
 void OmpStructureChecker::Leave(const parser::OmpAtomic &) {
@@ -3353,6 +3356,7 @@ void OmpStructureChecker::Leave(const parser::OmpAtomic &) {
         "Clause ACQ_REL is not allowed on the ATOMIC directive"_err_en_US);
   }
 }
+
 // Restrictions specific to each clause are implemented apart from the
 // generalized restrictions.
 void OmpStructureChecker::Enter(const parser::OmpClause::Aligned &x) {
@@ -3364,15 +3368,48 @@ void OmpStructureChecker::Enter(const parser::OmpClause::Aligned &x) {
   }
   // 2.8.1 TODO: list-item attribute check
 }
+
 void OmpStructureChecker::Enter(const parser::OmpClause::Defaultmap &x) {
   CheckAllowedClause(llvm::omp::Clause::OMPC_defaultmap);
+  unsigned version{context_.langOptions().OpenMPVersion};
+  using ImplicitBehavior = parser::OmpDefaultmapClause::ImplicitBehavior;
+  auto behavior{std::get<ImplicitBehavior>(x.v.t)};
+  if (version <= 45) {
+    if (behavior != ImplicitBehavior::Tofrom) {
+      context_.Say(GetContext().clauseSource,
+          "%s is not allowed in %s, %s"_warn_en_US,
+          parser::ToUpperCaseLetters(
+              parser::OmpDefaultmapClause::EnumToString(behavior)),
+          ThisVersion(version), TryVersion(50));
+    }
+  }
   using VariableCategory = parser::OmpDefaultmapClause::VariableCategory;
-  if (!std::get<std::optional<VariableCategory>>(x.v.t)) {
-    context_.Say(GetContext().clauseSource,
-        "The argument TOFROM:SCALAR must be specified on the DEFAULTMAP "
-        "clause"_err_en_US);
+  auto maybeCategory{std::get<std::optional<VariableCategory>>(x.v.t)};
+  if (!maybeCategory) {
+    if (version <= 45) {
+      context_.Say(GetContext().clauseSource,
+          "The DEFAULTMAP clause requires a variable-category SCALAR in %s, %s"_warn_en_US,
+          ThisVersion(version), TryVersion(50));
+    }
+  } else {
+    VariableCategory category{*maybeCategory};
+    unsigned tryVersion{0};
+    if (version <= 45 && category != VariableCategory::Scalar) {
+      tryVersion = 50;
+    }
+    if (version < 52 && category == VariableCategory::All) {
+      tryVersion = 52;
+    }
+    if (tryVersion) {
+      context_.Say(GetContext().clauseSource,
+          "%s is not allowed in %s, %s"_warn_en_US,
+          parser::ToUpperCaseLetters(
+              parser::OmpDefaultmapClause::EnumToString(category)),
+          ThisVersion(version), TryVersion(tryVersion));
+    }
   }
 }
+
 void OmpStructureChecker::Enter(const parser::OmpClause::If &x) {
   CheckAllowedClause(llvm::omp::Clause::OMPC_if);
   using dirNameModifier = parser::OmpIfClause::DirectiveNameModifier;
diff --git a/flang/test/Lower/OpenMP/Todo/defaultmap-clause.f90 b/flang/test/Lower/OpenMP/Todo/defaultmap-clause.f90
new file mode 100644
index 0000000000000..062399d9a1944
--- /dev/null
+++ b/flang/test/Lower/OpenMP/Todo/defaultmap-clause.f90
@@ -0,0 +1,8 @@
+!RUN: %not_todo_cmd bbc -emit-hlfir -fopenmp -fopenmp-version=45 -o - %s 2>&1 | FileCheck %s
+!RUN: %not_todo_cmd %flang_fc1 -emit-hlfir -fopenmp -fopenmp-version=45 -o - %s 2>&1 | FileCheck %s
+
+!CHECK: not yet implemented: DEFAULTMAP clause is not implemented yet
+subroutine f00
+  !$omp target defaultmap(tofrom:scalar)
+  !$omp end target
+end
diff --git a/flang/test/Lower/OpenMP/Todo/task_detach.f90 b/flang/test/Lower/OpenMP/Todo/task_detach.f90
index 6bc55e9e7cf64..cb6943073d4b3 100644
--- a/flang/test/Lower/OpenMP/Todo/task_detach.f90
+++ b/flang/test/Lower/OpenMP/Todo/task_detach.f90
@@ -6,7 +6,7 @@
 ! `detach` clause
 !===============================================================================
 
-! CHECK: not yet implemented: OpenMP Block construct clause
+! CHECK: not yet implemented: DETACH clause is not implemented yet
 subroutine omp_task_detach()
   use omp_lib
   integer (kind=omp_event_handle_kind) :: event
diff --git a/flang/test/Lower/OpenMP/Todo/task_untied.f90 b/flang/test/Lower/OpenMP/Todo/task_untied.f90
index 19621c7aac16d..87d242ba3e9d2 100644
--- a/flang/test/Lower/OpenMP/Todo/task_untied.f90
+++ b/flang/test/Lower/OpenMP/Todo/task_untied.f90
@@ -5,7 +5,7 @@
 ! `untied` clause
 !===============================================================================
 
-! CHECK: not yet implemented: OpenMP Block construct clause
+! CHECK: not yet implemented: UNTIED clause is not implemented yet
 subroutine omp_task_untied()
   !$omp task untied
   call foo()
diff --git a/flang/test/Parser/OpenMP/defaultmap-clause.f90 b/flang/test/Parser/OpenMP/defaultmap-clause.f90
new file mode 100644
index 0000000000000..6f018ffe8561c
--- /dev/null
+++ b/flang/test/Parser/OpenMP/defaultmap-clause.f90
@@ -0,0 +1,84 @@
+!RUN: %flang_fc1 -fdebug-unparse -fopenmp -fopenmp-version=52 %s | FileCheck --ignore-case --check-prefix="UNPARSE" %s
+!RUN: %flang_fc1 -fdebug-dump-parse-tree -fopenmp -fopenmp-version=52 %s | FileCheck --check-prefix="PARSE-TREE" %s
+
+subroutine f00
+  !$omp target defaultmap(from)
+  !$omp end target
+end
+
+!UNPARSE: SUBROUTINE f00
+!UNPARSE: !$OMP TARGET  DEFAULTMAP(FROM)
+!UNPARSE: !$OMP END TARGET
+!UNPARSE: END SUBROUTINE
+
+!PARSE-TREE: OmpBeginBlockDirective
+!PARSE-TREE: | OmpBlockDirective -> llvm::omp::Directive = target
+!PARSE-TREE: | OmpClauseList -> OmpClause -> Defaultmap -> OmpDefaultmapClause
+!PARSE-TREE: | | ImplicitBehavior = From
+!PARSE-TREE: Block
+
+subroutine f01
+  !$omp target defaultmap(firstprivate: aggregate)
+  !$omp end target
+end
+
+!UNPARSE: SUBROUTINE f01
+!UNPARSE: !$OMP TARGET  DEFAULTMAP(FIRSTPRIVATE:AGGREGATE)
+!UNPARSE: !$OMP END TARGET
+!UNPARSE: END SUBROUTINE
+
+!PARSE-TREE: OmpBeginBlockDirective
+!PARSE-TREE: | OmpBlockDirective -> llvm::omp::Directive = target
+!PARSE-TREE: | OmpClauseList -> OmpClause -> Defaultmap -> OmpDefaultmapClause
+!PARSE-TREE: | | ImplicitBehavior = Firstprivate
+!PARSE-TREE: | | VariableCategory = Aggregate
+
+subroutine f02
+  !$omp target defaultmap(alloc: all)
+  !$omp end target
+end
+
+!UNPARSE: SUBROUTINE f02
+!UNPARSE: !$OMP TARGET  DEFAULTMAP(ALLOC:ALL)
+!UNPARSE: !$OMP END TARGET
+!UNPARSE: END SUBROUTINE
+
+!PARSE-TREE: OmpBeginBlockDirective
+!PARSE-TREE: | OmpBlockDirective -> llvm::omp::Directive = target
+!PARSE-TREE: | OmpClauseList -> OmpClause -> Defaultmap -> OmpDefaultmapClause
+!PARSE-TREE: | | ImplicitBehavior = Alloc
+!PARSE-TREE: | | VariableCategory = All
+
+! Both "all" and "allocatable" are valid, and "all" is a prefix of
+! "allocatable". Make sure we parse this correctly.
+subroutine f03
+  !$omp target defaultmap(alloc: allocatable)
+  !$omp end target
+end
+
+!UNPARSE: SUBROUTINE f03
+!UNPARSE: !$OMP TARGET  DEFAULTMAP(ALLOC:ALLOCATABLE)
+!UNPARSE: !$OMP END TARGET
+!UNPARSE: END SUBROUTINE
+
+!PARSE-TREE: OmpBeginBlockDirective
+!PARSE-TREE: | OmpBlockDirective -> llvm::omp::Directive = target
+!PARSE-TREE: | OmpClauseList -> OmpClause -> Defaultmap -> OmpDefaultmapClause
+!PARSE-TREE: | | ImplicitBehavior = Alloc
+!PARSE-TREE: | | VariableCategory = Allocatable
+
+subroutine f04
+  !$omp target defaultmap(tofrom: scalar)
+  !$omp end target
+end
+
+!UNPARSE: SUBROUTINE f04
+!UNPARSE: !$OMP TARGET  DEFAULTMAP(TOFROM:SCALAR)
+!UNPARSE: !$OMP END TARGET
+!UNPARSE: END SUBROUTINE
+
+!PARSE-TREE: OmpBeginBlockDirective
+!PARSE-TREE: | OmpBlockDirective -> llvm::omp::Directive = target
+!PARSE-TREE: | OmpClauseList -> OmpClause -> Defaultmap -> OmpDefaultmapClause
+!PARSE-TREE: | | ImplicitBehavior = Tofrom
+!PARSE-TREE: | | VariableCategory = Scalar
diff --git a/flang/test/Semantics/OpenMP/combined-constructs.f90 b/flang/test/Semantics/OpenMP/combined-constructs.f90
index b7a3848215930..38b0d090e441d 100644
--- a/flang/test/Semantics/OpenMP/combined-constructs.f90
+++ b/flang/test/Semantics/OpenMP/combined-constructs.f90
@@ -33,7 +33,7 @@ program main
   enddo
   !$omp end target parallel
 
-  !ERROR: The argument TOFROM:SCALAR must be specified on the DEFAULTMAP clause
+  !ERROR: The DEFAULTMAP clause requires a variable-category SCALAR in OpenMP v1.1, try -fopenmp-version=50
   !$omp target parallel defaultmap(tofrom)
   do i = 1, N
      a(i) = 3.14
@@ -80,7 +80,7 @@ program main
   enddo
   !$omp end target parallel do
 
-  !ERROR: The argument TOFROM:SCALAR must be specified on the DEFAULTMAP clause
+  !ERROR: The DEFAULTMAP clause requires a variable-category SCALAR in OpenMP v1.1, try -fopenmp-version=50
   !$omp target parallel do defaultmap(tofrom)
   do i = 1, N
      a(i) = 3.14
@@ -140,7 +140,7 @@ program main
   enddo
   !$omp end target teams
 
-  !ERROR: The argument TOFROM:SCALAR must be specified on the DEFAULTMAP clause
+  !ERROR: The DEFAULTMAP clause requires a variable-category SCALAR in OpenMP v1.1, try -fopenmp-version=50
   !$omp target teams defaultmap(tofrom)
   do i = 1, N
      a(i) = 3.14
@@ -240,7 +240,7 @@ program main
   enddo
   !$omp end target teams distribute
 
-  !ERROR: The argument TOFROM:SCALAR must be specified on the DEFAULTMAP clause
+  !ERROR: The DEFAULTMAP clause requires a variable-category SCALAR in OpenMP v1.1, try -fopenmp-version=50
   !$omp target teams distribute defaultmap(tofrom)
   do i = 1, N
      a(i) = 3.14
@@ -333,7 +333,7 @@ program main
   enddo
   !$omp end target teams distribute parallel do
 
-  !ERROR: The argument TOFROM:SCALAR must be specified on the DEFAULTMAP clause
+  !ERROR: The DEFAULTMAP clause requires a variable-category SCALAR in OpenMP v1.1, try -fopenmp-version=50
   !$omp target teams distribute parallel do defaultmap(tofrom)
   do i = 1, N
      a(i) = 3.14
@@ -433,7 +433,7 @@ program main
   enddo
   !$omp end target teams distribute parallel do simd
 
-  !ERROR: The argument TOFROM:SCALAR must be specified on the DEFAULTMAP clause
+  !ERROR: The DEFAULTMAP clause requires a variable-category SCALAR in OpenMP v1.1, try -fopenmp-version=50
   !$omp target teams distribute parallel do simd defaultmap(tofrom)
   do i = 1, N
      a(i) = 3.14
diff --git a/flang/test/Semantics/OpenMP/defaultmap-clause-v45.f90 b/flang/test/Semantics/OpenMP/defaultmap-clause-v45.f90
new file mode 100644
index 0000000000000..a30d90ddce029
--- /dev/null
+++ b/flang/test/Semantics/OpenMP/defaultmap-clause-v45.f90
@@ -0,0 +1,34 @@
+!RUN: %python %S/../test_errors.py %s %flang -fopenmp -fopenmp-version=45 -Werror
+
+subroutine f00
+!WARNING: The DEFAULTMAP clause requires a variable-category SCALAR in OpenMP v4.5, try -fopenmp-version=50
+  !$omp target defaultmap(tofrom)
+  !$omp end target
+end
+
+subroutine f01
+!WARNING: AGGREGATE is not allowed in OpenMP v4.5, try -fopenmp-version=50
+  !$omp target defaultmap(tofrom:aggregate)
+  !$omp end target
+end
+
+subroutine f02
+!WARNING: FROM is not allowed in OpenMP v4.5, try -fopenmp-version=50
+  !$omp target defaultmap(from:scalar)
+  !$omp end target
+end
+
+subroutine f03
+!WARNING: ALL is not allowed in OpenMP v4.5, try -fopenmp-version=52
+  !$omp target defaultmap(tofrom:all)
+  !$omp end target
+end
+
+subroutine f04
+!WARNING: FROM is not allowed in OpenMP v4.5, try -fopenmp-version=50
+!WARNING: POINTER is not allowed in OpenMP v4.5, try -fopenmp-version=50
+  !$omp target defaultmap(from:pointer)
+  !$omp end target
+end
+
+
diff --git a/flang/test/Semantics/OpenMP/defaultmap-clause-v50.f90 b/flang/test/Semantics/OpenMP/defaultmap-clause-v50.f90
new file mode 100644
index 0000000000000..57bb207bb797a
--- /dev/null
+++ b/flang/test/Semantics/OpenMP/defaultmap-clause-v50.f90
@@ -0,0 +1,23 @@
+!RUN: %python %S/../test_errors.py %s %flang -fopenmp -fopenmp-version=50 -Werror
+
+subroutine f00
+  !$omp target defaultmap(tofrom)
+  !$omp end target
+end
+
+subroutine f01
+  !$omp target defaultmap(tofrom:aggregate)
+  !$omp end target
+end
+
+subroutine f02
+  !$omp target defaultmap(from:scalar)
+  !$omp end target
+end
+
+subroutine f03
+!WARNING: ALL is not allowed in OpenMP v5.0, try -fopenmp-version=52
+  !$omp target defaultmap(tofrom:all)
+  !$omp end target
+end
+
diff --git a/flang/test/Semantics/OpenMP/device-constructs.f90 b/flang/test/Semantics/OpenMP/device-constructs.f90
index 4047fbf3fa811..6f545b9021966 100644
--- a/flang/test/Semantics/OpenMP/device-constructs.f90
+++ b/flang/test/Semantics/OpenMP/device-constructs.f90
@@ -44,7 +44,6 @@ program main
   enddo
   !$omp end target
 
-  !ERROR: The argument TOFROM:SCALAR must be specified on the DEFAULTMAP clause
   !$omp target defaultmap(tofrom)
   do i = 1, N
      a = 3.14
diff --git a/llvm/include/llvm/Frontend/OpenMP/ClauseT.h b/llvm/include/llvm/Frontend/OpenMP/ClauseT.h
index f4e089db0080e..ce09bb5f730a7 100644
--- a/llvm/include/llvm/Frontend/OpenMP/ClauseT.h
+++ b/llvm/include/llvm/Frontend/OpenMP/ClauseT.h
@@ -490,7 +490,7 @@ template <typename T, typename I, typename E> //
 struct DefaultmapT {
   ENUM(ImplicitBehavior, Alloc, To, From, Tofrom, Firstprivate, None, Default,
        Present);
-  ENUM(VariableCategory, Scalar, Aggregate, Pointer, Allocatable);
+  ENUM(VariableCategory, All, Scalar, Aggregate, Pointer, Allocatable);
   using TupleTrait = std::true_type;
   std::tuple<ImplicitBehavior, OPT(VariableCategory)> t;
 };