diff --git a/flang/test/Semantics/acc-clause-validity.f90 b/flang/test/Semantics/acc-clause-validity.f90
--- a/flang/test/Semantics/acc-clause-validity.f90
+++ b/flang/test/Semantics/acc-clause-validity.f90
@@ -25,9 +25,11 @@
   integer, parameter :: N = 256
   integer, dimension(N) :: c
   logical, dimension(N) :: d, e
+  integer :: async1
+  integer :: wait1, wait2
   real :: reduction_r
   logical :: reduction_l
-  real(8), dimension(N, N) :: aa
+  real(8), dimension(N, N) :: aa, bb, cc
   logical :: ifCondition = .TRUE.
 
   !ERROR: At least one clause is required on the DECLARE directive
@@ -365,6 +367,141 @@
   end do
   !$acc end kernels loop
 
+  !$acc serial
+  !$acc end serial
+
+  !$acc serial async
+  !$acc end serial
+
+  !$acc serial async(1)
+  !$acc end serial
+
+  !$acc serial async(async1)
+  !$acc end serial
+
+  !$acc serial wait
+  !$acc end serial
+
+  !$acc serial wait(1)
+  !$acc end serial
+
+  !$acc serial wait(wait1)
+  !$acc end serial
+
+  !$acc serial wait(1,2)
+  !$acc end serial
+
+  !$acc serial wait(wait1, wait2)
+  !$acc end serial
+
+  !$acc serial if(.true.)
+  !$acc end serial
+
+  !ERROR: At most one IF clause can appear on the SERIAL directive
+  !$acc serial if(.true.) if(ifCondition)
+  !$acc end serial
+
+  !$acc serial if(ifCondition)
+  !$acc end serial
+
+  !$acc serial self
+  !$acc end serial
+
+  !$acc serial self(.true.)
+  !$acc end serial
+
+  !$acc serial self(ifCondition)
+  !$acc end serial
+
+  !$acc serial loop reduction(+: reduction_r)
+  do i = 1, N
+    reduction_r = a(i) + i
+  end do
+
+  !$acc serial loop reduction(*: reduction_r)
+  do i = 1, N
+    reduction_r = reduction_r * (a(i) + i)
+  end do
+
+  !$acc serial loop reduction(min: reduction_r)
+  do i = 1, N
+    reduction_r = min(reduction_r, a(i) * i)
+  end do
+
+  !$acc serial loop reduction(max: reduction_r)
+  do i = 1, N
+    reduction_r = max(reduction_r, a(i) * i)
+  end do
+
+  !$acc serial loop reduction(iand: b)
+  do i = 1, N
+    b = iand(b, c(i))
+  end do
+
+  !$acc serial loop reduction(ior: b)
+  do i = 1, N
+    b = ior(b, c(i))
+  end do
+
+  !$acc serial loop reduction(ieor: b)
+  do i = 1, N
+    b = ieor(b, c(i))
+  end do
+
+  !$acc serial loop reduction(.and.: reduction_l)
+  do i = 1, N
+    reduction_l = d(i) .and. e(i)
+  end do
+
+  !$acc serial loop reduction(.or.: reduction_l)
+  do i = 1, N
+    reduction_l = d(i) .or. e(i)
+  end do
+
+  !$acc serial loop reduction(.eqv.: reduction_l)
+  do i = 1, N
+    reduction_l = d(i) .eqv. e(i)
+  end do
+
+  !$acc serial loop reduction(.neqv.: reduction_l)
+  do i = 1, N
+    reduction_l = d(i) .neqv. e(i)
+  end do
+
+  !$acc serial copy(aa) copyin(bb) copyout(cc)
+  !$acc end serial
+
+  !$acc serial copy(aa, bb) copyout(zero: cc)
+  !$acc end serial
+
+  !$acc serial present(aa, bb) create(cc)
+  !$acc end serial
+
+  !$acc serial copyin(readonly: aa, bb) create(zero: cc)
+  !$acc end serial
+
+  !$acc serial deviceptr(aa, bb) no_create(cc)
+  !$acc end serial
+
+  !$acc serial attach(aa, bb, cc)
+  !$acc end serial
+
+  !$acc serial private(aa) firstprivate(bb, cc)
+  !$acc end serial
+
+  !$acc serial default(none)
+  !$acc end serial
+
+  !$acc serial default(present)
+  !$acc end serial
+
+  !ERROR: At most one DEFAULT clause can appear on the SERIAL directive
+  !$acc serial default(present) default(none)
+  !$acc end serial
+
+  !$acc serial device_type(*) async wait
+  !$acc end serial
+
   !$acc serial device_type(*) async
   do i = 1, N
     a(i) = 3.14
@@ -473,6 +610,8 @@
   !$acc kernels wait(devnum: 1: queues: 1, 2) async(3)
   !$acc end kernels
 
+
+
   !$acc wait
 
   !$acc wait async