diff --git a/gcc/c/c-typeck.c b/gcc/c/c-typeck.c
index 385bf3a1c7b..134f1520239 100644
--- a/gcc/c/c-typeck.c
+++ b/gcc/c/c-typeck.c
@@ -14533,6 +14533,10 @@ c_finish_omp_clauses (tree clauses, enum c_omp_region_type ort)
 		}
 	      if (c_oacc_check_attachments (c))
 		remove = true;
+	      if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_MAP
+		  && (OMP_CLAUSE_MAP_KIND (c) == GOMP_MAP_ATTACH
+		      || OMP_CLAUSE_MAP_KIND (c) == GOMP_MAP_DETACH))
+		OMP_CLAUSE_SIZE (c) = size_zero_node;
 	      break;
 	    }
 	  if (t == error_mark_node)
@@ -14546,6 +14550,10 @@ c_finish_omp_clauses (tree clauses, enum c_omp_region_type ort)
 	      remove = true;
 	      break;
 	    }
+	  if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_MAP
+	      && (OMP_CLAUSE_MAP_KIND (c) == GOMP_MAP_ATTACH
+		  || OMP_CLAUSE_MAP_KIND (c) == GOMP_MAP_DETACH))
+	    OMP_CLAUSE_SIZE (c) = size_zero_node;
 	  if (TREE_CODE (t) == COMPONENT_REF
 	      && OMP_CLAUSE_CODE (c) != OMP_CLAUSE__CACHE_)
 	    {
diff --git a/gcc/cp/semantics.c b/gcc/cp/semantics.c
index 64587c791c6..77e6ff7fb0d 100644
--- a/gcc/cp/semantics.c
+++ b/gcc/cp/semantics.c
@@ -7334,6 +7334,10 @@ finish_omp_clauses (tree clauses, enum c_omp_region_type ort)
 		}
 	      if (cp_oacc_check_attachments (c))
 		remove = true;
+	      if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_MAP
+		  && (OMP_CLAUSE_MAP_KIND (c) == GOMP_MAP_ATTACH
+		      || OMP_CLAUSE_MAP_KIND (c) == GOMP_MAP_DETACH))
+		OMP_CLAUSE_SIZE (c) = size_zero_node;
 	      break;
 	    }
 	  if (t == error_mark_node)
@@ -7347,6 +7351,10 @@ finish_omp_clauses (tree clauses, enum c_omp_region_type ort)
 	      remove = true;
 	      break;
 	    }
+	  if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_MAP
+	      && (OMP_CLAUSE_MAP_KIND (c) == GOMP_MAP_ATTACH
+		  || OMP_CLAUSE_MAP_KIND (c) == GOMP_MAP_DETACH))
+	    OMP_CLAUSE_SIZE (c) = size_zero_node;
 	  if (REFERENCE_REF_P (t)
 	      && TREE_CODE (TREE_OPERAND (t, 0)) == COMPONENT_REF)
 	    {
diff --git a/gcc/testsuite/c-c++-common/goacc/mdc-1.c b/gcc/testsuite/c-c++-common/goacc/mdc-1.c
index fb5841a709d..337c1f7cc77 100644
--- a/gcc/testsuite/c-c++-common/goacc/mdc-1.c
+++ b/gcc/testsuite/c-c++-common/goacc/mdc-1.c
@@ -45,12 +45,12 @@ t1 ()
 
 /* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.to:s .len: 32.." 1 "omplower" } } */
 /* { dg-final { scan-tree-dump-times "pragma omp target oacc_data map.tofrom:.z .len: 40.. map.struct:s .len: 1.. map.alloc:s.a .len: 8.. map.tofrom:._1 .len: 40.. map.attach:s.a .bias: 0.." 1 "omplower" } } */
-/* { dg-final { scan-tree-dump-times "pragma omp target oacc_parallel map.attach:s.e .bias: 8.. map.tofrom:s .len: 32" 1 "omplower" } } */
-/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.attach:a .bias: 8.." 1 "omplower" } } */
-/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.detach:a .bias: 8.." 1 "omplower" } } */
+/* { dg-final { scan-tree-dump-times "pragma omp target oacc_parallel map.attach:s.e .bias: 0.. map.tofrom:s .len: 32" 1 "omplower" } } */
+/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.attach:a .bias: 0.." 1 "omplower" } } */
+/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.detach:a .bias: 0.." 1 "omplower" } } */
 /* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.to:a .len: 8.." 1 "omplower" } } */
-/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.detach:s.e .bias: 8.." 1 "omplower" } } */
-/* { dg-final { scan-tree-dump-times "pragma omp target oacc_data map.attach:s.e .bias: 8.." 1 "omplower" } } */
+/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.detach:s.e .bias: 0.." 1 "omplower" } } */
+/* { dg-final { scan-tree-dump-times "pragma omp target oacc_data map.attach:s.e .bias: 0.." 1 "omplower" } } */
 /* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data map.release:a .len: 8.." 1 "omplower" } } */
-/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data finalize map.force_detach:a .bias: 8.." 1 "omplower" } } */
-/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data finalize map.force_detach:s.a .bias: 8.." 1 "omplower" } } */
+/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data finalize map.force_detach:a .bias: 0.." 1 "omplower" } } */
+/* { dg-final { scan-tree-dump-times "pragma omp target oacc_enter_exit_data finalize map.force_detach:s.a .bias: 0.." 1 "omplower" } } */
