diff --git a/flang/include/flang/Optimizer/Builder/BoxValue.h b/flang/include/flang/Optimizer/Builder/BoxValue.h
index 5c7e89dbc08f1..9fdaa0b197179 100644
--- a/flang/include/flang/Optimizer/Builder/BoxValue.h
+++ b/flang/include/flang/Optimizer/Builder/BoxValue.h
@@ -433,7 +433,8 @@ llvm::raw_ostream &operator<<(llvm::raw_ostream &, const ExtendedValue &);
 /// substituted.
 ExtendedValue substBase(const ExtendedValue &exv, mlir::Value base);
 
-/// Is the extended value `exv` an array?
+/// Is the extended value `exv` an array? Note that this returns true for
+/// assumed-ranks that could actually be scalars at runtime.
 bool isArray(const ExtendedValue &exv);
 
 /// Get the type parameters for `exv`.
@@ -527,6 +528,15 @@ class ExtendedValue : public details::matcher<ExtendedValue> {
                  [](const auto &box) -> bool { return false; });
   }
 
+  bool hasAssumedRank() const {
+    return match(
+        [](const fir::BoxValue &box) -> bool { return box.hasAssumedRank(); },
+        [](const fir::MutableBoxValue &box) -> bool {
+          return box.hasAssumedRank();
+        },
+        [](const auto &box) -> bool { return false; });
+  }
+
   /// LLVM style debugging of extended values
   LLVM_DUMP_METHOD void dump() const { llvm::errs() << *this << '\n'; }
 
diff --git a/flang/lib/Optimizer/Builder/IntrinsicCall.cpp b/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
index 072899751bc8a..1606bb6559e65 100644
--- a/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
+++ b/flang/lib/Optimizer/Builder/IntrinsicCall.cpp
@@ -6086,9 +6086,6 @@ IntrinsicLibrary::genSize(mlir::Type resultType,
   // Note that the value of the KIND argument is already reflected in the
   // resultType
   assert(args.size() == 3);
-  if (const auto *boxValue = args[0].getBoxOf<fir::BoxValue>())
-    if (boxValue->hasAssumedRank())
-      TODO(loc, "intrinsic: size with assumed rank argument");
 
   // Get the ARRAY argument
   mlir::Value array = builder.createBox(loc, args[0]);
@@ -6102,13 +6099,15 @@ IntrinsicLibrary::genSize(mlir::Type resultType,
 
   // Get the DIM argument.
   mlir::Value dim = fir::getBase(args[1]);
-  if (std::optional<std::int64_t> cstDim = fir::getIntIfConstant(dim)) {
-    // If it is a compile time constant, skip the runtime call.
-    return builder.createConvert(loc, resultType,
-                                 fir::factory::readExtent(builder, loc,
-                                                          fir::BoxValue{array},
-                                                          cstDim.value() - 1));
-  }
+  if (!args[0].hasAssumedRank())
+    if (std::optional<std::int64_t> cstDim = fir::getIntIfConstant(dim)) {
+      // If both DIM and the rank are compile time constants, skip the runtime
+      // call.
+      return builder.createConvert(
+          loc, resultType,
+          fir::factory::readExtent(builder, loc, fir::BoxValue{array},
+                                   cstDim.value() - 1));
+    }
   if (!fir::isa_ref_type(dim.getType()))
     return builder.createConvert(
         loc, resultType, fir::runtime::genSizeDim(builder, loc, array, dim));
diff --git a/flang/test/Lower/HLFIR/assumed-rank-inquiries-2.f90 b/flang/test/Lower/HLFIR/assumed-rank-inquiries-2.f90
new file mode 100644
index 0000000000000..353e944a8ac18
--- /dev/null
+++ b/flang/test/Lower/HLFIR/assumed-rank-inquiries-2.f90
@@ -0,0 +1,108 @@
+! Test lowering of SIZE/SIZEOF inquiry intrinsics with assumed-ranks
+! arguments.
+! RUN: bbc -emit-hlfir -o - %s -allow-assumed-rank | FileCheck %s
+
+
+subroutine test_size_1(x)
+  real :: x(..)
+  call takes_integer(size(x))
+end subroutine
+
+subroutine test_size_2(x)
+  real :: x(..)
+  call takes_integer(size(x, 2))
+end subroutine
+
+subroutine test_size_3(x, d)
+  real :: x(..)
+  integer, optional :: d
+  call takes_integer(size(x, d))
+end subroutine
+
+subroutine test_size_4(x)
+  real, allocatable :: x(..)
+  call takes_integer(size(x))
+end subroutine
+
+
+! CHECK-LABEL:   func.func @_QPtest_size_1(
+! CHECK-SAME:                              %[[VAL_0:.*]]: !fir.box<!fir.array<*:f32>> {fir.bindc_name = "x"}) {
+! CHECK:           %[[VAL_1:.*]] = fir.dummy_scope : !fir.dscope
+! CHECK:           %[[VAL_2:.*]]:2 = hlfir.declare %[[VAL_0]] dummy_scope %[[VAL_1]] {uniq_name = "_QFtest_size_1Ex"} : (!fir.box<!fir.array<*:f32>>, !fir.dscope) -> (!fir.box<!fir.array<*:f32>>, !fir.box<!fir.array<*:f32>>)
+! CHECK:           %[[VAL_5:.*]] = fir.convert %[[VAL_2]]#1 : (!fir.box<!fir.array<*:f32>>) -> !fir.box<none>
+! CHECK:           %[[VAL_7:.*]] = fir.call @_FortranASize(%[[VAL_5]]
+! CHECK:           %[[VAL_8:.*]] = fir.convert %[[VAL_7]] : (i64) -> i32
+! CHECK:           %[[VAL_9:.*]]:3 = hlfir.associate %[[VAL_8]] {adapt.valuebyref} : (i32) -> (!fir.ref<i32>, !fir.ref<i32>, i1)
+! CHECK:           fir.call @_QPtakes_integer(%[[VAL_9]]#1) fastmath<contract> : (!fir.ref<i32>) -> ()
+! CHECK:           hlfir.end_associate %[[VAL_9]]#1, %[[VAL_9]]#2 : !fir.ref<i32>, i1
+! CHECK:           return
+! CHECK:         }
+
+! CHECK-LABEL:   func.func @_QPtest_size_2(
+! CHECK-SAME:                              %[[VAL_0:.*]]: !fir.box<!fir.array<*:f32>> {fir.bindc_name = "x"}) {
+! CHECK:           %[[VAL_1:.*]] = fir.alloca i32
+! CHECK:           %[[VAL_2:.*]] = fir.dummy_scope : !fir.dscope
+! CHECK:           %[[VAL_3:.*]]:2 = hlfir.declare %[[VAL_0]] dummy_scope %[[VAL_2]] {uniq_name = "_QFtest_size_2Ex"} : (!fir.box<!fir.array<*:f32>>, !fir.dscope) -> (!fir.box<!fir.array<*:f32>>, !fir.box<!fir.array<*:f32>>)
+! CHECK:           %[[VAL_4:.*]] = arith.constant 2 : i32
+! CHECK:           fir.store %[[VAL_4]] to %[[VAL_1]] : !fir.ref<i32>
+! CHECK:           %[[VAL_5:.*]] = fir.convert %[[VAL_1]] : (!fir.ref<i32>) -> i64
+! CHECK:           %[[VAL_6:.*]] = arith.constant 0 : i64
+! CHECK:           %[[VAL_7:.*]] = arith.cmpi eq, %[[VAL_5]], %[[VAL_6]] : i64
+! CHECK:           %[[VAL_8:.*]] = fir.if %[[VAL_7]] -> (i32) {
+! CHECK:             %[[VAL_11:.*]] = fir.convert %[[VAL_3]]#1 : (!fir.box<!fir.array<*:f32>>) -> !fir.box<none>
+! CHECK:             %[[VAL_13:.*]] = fir.call @_FortranASize(%[[VAL_11]]
+! CHECK:             %[[VAL_14:.*]] = fir.convert %[[VAL_13]] : (i64) -> i32
+! CHECK:             fir.result %[[VAL_14]] : i32
+! CHECK:           } else {
+! CHECK:             %[[VAL_15:.*]] = fir.load %[[VAL_1]] : !fir.ref<i32>
+! CHECK:             %[[VAL_18:.*]] = fir.convert %[[VAL_3]]#1 : (!fir.box<!fir.array<*:f32>>) -> !fir.box<none>
+! CHECK:             %[[VAL_20:.*]] = fir.call @_FortranASizeDim(%[[VAL_18]]
+! CHECK:             %[[VAL_21:.*]] = fir.convert %[[VAL_20]] : (i64) -> i32
+! CHECK:             fir.result %[[VAL_21]] : i32
+! CHECK:           }
+! CHECK:           %[[VAL_22:.*]]:3 = hlfir.associate %[[VAL_8]] {adapt.valuebyref} : (i32) -> (!fir.ref<i32>, !fir.ref<i32>, i1)
+! CHECK:           fir.call @_QPtakes_integer(%[[VAL_22]]#1) fastmath<contract> : (!fir.ref<i32>) -> ()
+! CHECK:           hlfir.end_associate %[[VAL_22]]#1, %[[VAL_22]]#2 : !fir.ref<i32>, i1
+! CHECK:           return
+! CHECK:         }
+
+! CHECK-LABEL:   func.func @_QPtest_size_3(
+! CHECK-SAME:                              %[[VAL_0:.*]]: !fir.box<!fir.array<*:f32>> {fir.bindc_name = "x"},
+! CHECK-SAME:                              %[[VAL_1:.*]]: !fir.ref<i32> {fir.bindc_name = "d", fir.optional}) {
+! CHECK:           %[[VAL_2:.*]] = fir.dummy_scope : !fir.dscope
+! CHECK:           %[[VAL_3:.*]]:2 = hlfir.declare %[[VAL_1]] dummy_scope %[[VAL_2]] {fortran_attrs = #fir.var_attrs<optional>, uniq_name = "_QFtest_size_3Ed"} : (!fir.ref<i32>, !fir.dscope) -> (!fir.ref<i32>, !fir.ref<i32>)
+! CHECK:           %[[VAL_4:.*]]:2 = hlfir.declare %[[VAL_0]] dummy_scope %[[VAL_2]] {uniq_name = "_QFtest_size_3Ex"} : (!fir.box<!fir.array<*:f32>>, !fir.dscope) -> (!fir.box<!fir.array<*:f32>>, !fir.box<!fir.array<*:f32>>)
+! CHECK:           %[[VAL_5:.*]] = fir.convert %[[VAL_3]]#1 : (!fir.ref<i32>) -> i64
+! CHECK:           %[[VAL_6:.*]] = arith.constant 0 : i64
+! CHECK:           %[[VAL_7:.*]] = arith.cmpi eq, %[[VAL_5]], %[[VAL_6]] : i64
+! CHECK:           %[[VAL_8:.*]] = fir.if %[[VAL_7]] -> (i32) {
+! CHECK:             %[[VAL_11:.*]] = fir.convert %[[VAL_4]]#1 : (!fir.box<!fir.array<*:f32>>) -> !fir.box<none>
+! CHECK:             %[[VAL_13:.*]] = fir.call @_FortranASize(%[[VAL_11]],
+! CHECK:             %[[VAL_14:.*]] = fir.convert %[[VAL_13]] : (i64) -> i32
+! CHECK:             fir.result %[[VAL_14]] : i32
+! CHECK:           } else {
+! CHECK:             %[[VAL_15:.*]] = fir.load %[[VAL_3]]#1 : !fir.ref<i32>
+! CHECK:             %[[VAL_18:.*]] = fir.convert %[[VAL_4]]#1 : (!fir.box<!fir.array<*:f32>>) -> !fir.box<none>
+! CHECK:             %[[VAL_20:.*]] = fir.call @_FortranASizeDim(%[[VAL_18]]
+! CHECK:             %[[VAL_21:.*]] = fir.convert %[[VAL_20]] : (i64) -> i32
+! CHECK:             fir.result %[[VAL_21]] : i32
+! CHECK:           }
+! CHECK:           %[[VAL_22:.*]]:3 = hlfir.associate %[[VAL_8]] {adapt.valuebyref} : (i32) -> (!fir.ref<i32>, !fir.ref<i32>, i1)
+! CHECK:           fir.call @_QPtakes_integer(%[[VAL_22]]#1) fastmath<contract> : (!fir.ref<i32>) -> ()
+! CHECK:           hlfir.end_associate %[[VAL_22]]#1, %[[VAL_22]]#2 : !fir.ref<i32>, i1
+! CHECK:           return
+! CHECK:         }
+
+! CHECK-LABEL:   func.func @_QPtest_size_4(
+! CHECK-SAME:                              %[[VAL_0:.*]]: !fir.ref<!fir.box<!fir.heap<!fir.array<*:f32>>>> {fir.bindc_name = "x"}) {
+! CHECK:           %[[VAL_1:.*]] = fir.dummy_scope : !fir.dscope
+! CHECK:           %[[VAL_2:.*]]:2 = hlfir.declare %[[VAL_0]] dummy_scope %[[VAL_1]] {fortran_attrs = #fir.var_attrs<allocatable>, uniq_name = "_QFtest_size_4Ex"} : (!fir.ref<!fir.box<!fir.heap<!fir.array<*:f32>>>>, !fir.dscope) -> (!fir.ref<!fir.box<!fir.heap<!fir.array<*:f32>>>>, !fir.ref<!fir.box<!fir.heap<!fir.array<*:f32>>>>)
+! CHECK:           %[[VAL_3:.*]] = fir.load %[[VAL_2]]#1 : !fir.ref<!fir.box<!fir.heap<!fir.array<*:f32>>>>
+! CHECK:           %[[VAL_6:.*]] = fir.convert %[[VAL_3]] : (!fir.box<!fir.heap<!fir.array<*:f32>>>) -> !fir.box<none>
+! CHECK:           %[[VAL_8:.*]] = fir.call @_FortranASize(%[[VAL_6]]
+! CHECK:           %[[VAL_9:.*]] = fir.convert %[[VAL_8]] : (i64) -> i32
+! CHECK:           %[[VAL_10:.*]]:3 = hlfir.associate %[[VAL_9]] {adapt.valuebyref} : (i32) -> (!fir.ref<i32>, !fir.ref<i32>, i1)
+! CHECK:           fir.call @_QPtakes_integer(%[[VAL_10]]#1) fastmath<contract> : (!fir.ref<i32>) -> ()
+! CHECK:           hlfir.end_associate %[[VAL_10]]#1, %[[VAL_10]]#2 : !fir.ref<i32>, i1
+! CHECK:           return
+! CHECK:         }