[flang] Fix character function call bug (#67973)

Fixes #67658

The bug was that when instantiating a character array result variable,
the code inserted a cast from the result buffer to the proper array type
if it could see an fir.unboxchar op. But this is wrong for results and
on caller side because the fir.emboxchar is visible so,
charHelper.genUnboxChar() just takes the operand from that instead of
generating an unboxchar.

The fix is simply to move the cast at the place where fir.boxchar<>
argument are dealt with. The cast when creating fir.emboxchar is also
removed: it adds noise and causes constant length result type to be
lowered to fir.char<?>.

The main change from this patch is to deal with the lit test fallout of
this cast move and removal.

Author: jeanPerier

flang/lib/Lower/ConvertVariable.cpp

@@ -1927,8 +1927,13 @@ void Fortran::lower::mapSymbolAttributes(
   if (ba.isChar()) {
     if (arg) {
       assert(!preAlloc && "dummy cannot be pre-allocated");
-      if (arg.getType().isa<fir::BoxCharType>())
+      if (arg.getType().isa<fir::BoxCharType>()) {
         std::tie(addr, len) = charHelp.createUnboxChar(arg);
+        // Ensure proper type is given to array/scalar that transited via
+        // fir.boxchar arg.
+        mlir::Type castTy = builder.getRefType(converter.genType(var));
+        addr = builder.createConvert(loc, castTy, addr);
+      }
     }
     if (std::optional<int64_t> cstLen = ba.getCharLenConst()) {
       // Static length
@@ -1954,13 +1959,6 @@ void Fortran::lower::mapSymbolAttributes(
     }
   }
 
-  if (addr && addr.getDefiningOp<fir::UnboxCharOp>()) {
-    // Ensure proper type is given to array/scalar that transited via
-    // fir.boxchar arg.
-    mlir::Type castTy = builder.getRefType(converter.genType(var));
-    addr = builder.createConvert(loc, castTy, addr);
-  }
-
   // Compute array extents and lower bounds.
   if (ba.isArray()) {
     if (ba.isStaticArray()) {

flang/lib/Optimizer/Builder/Character.cpp

@@ -208,7 +208,9 @@ fir::factory::CharacterExprHelper::createEmbox(const fir::CharBoxValue &box) {
     builder.create<fir::StoreOp>(loc, buff, temp);
     buff = temp;
   }
-  buff = builder.createConvert(loc, refType, buff);
+  // fir.emboxchar only accepts scalar, cast array buffer to a scalar buffer.
+  if (mlir::isa<fir::SequenceType>(fir::dyn_cast_ptrEleTy(buff.getType())))
+    buff = builder.createConvert(loc, refType, buff);
   // Convert in case the provided length is not of the integer type that must
   // be used in boxchar.
   auto len = builder.createConvert(loc, builder.getCharacterLengthType(),

flang/test/Lower/HLFIR/bindc-entry-stmt.f90

@@ -24,15 +24,14 @@ function foo() bind(c)
 ! CHECK-LABEL:   func.func @_QPbar(
 ! CHECK-SAME:                      %[[VAL_0:.*]]: !fir.ref<!fir.char<1>>,
 ! CHECK-SAME:                      %[[VAL_1:.*]]: index) -> !fir.boxchar<1> {
-! CHECK:           %[[VAL_2:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<!fir.char<1>>) -> !fir.ref<!fir.char<1,?>>
 ! CHECK:           %[[VAL_3:.*]] = arith.constant 1 : index
-! CHECK:           %[[VAL_4:.*]]:2 = hlfir.declare %[[VAL_2]] typeparams %[[VAL_3]] {uniq_name = "_QFfooEfoo"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
+! CHECK:           %[[VAL_4:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_3]] {uniq_name = "_QFfooEfoo"} : (!fir.ref<!fir.char<1>>, index) -> (!fir.ref<!fir.char<1>>, !fir.ref<!fir.char<1>>)
 ! CHECK:           %[[VAL_5:.*]] = arith.constant 1 : index
-! CHECK:           %[[VAL_6:.*]]:2 = hlfir.declare %[[VAL_2]] typeparams %[[VAL_5]] {uniq_name = "_QFfooEbar"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
+! CHECK:           %[[VAL_6:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_5]] {uniq_name = "_QFfooEbar"} : (!fir.ref<!fir.char<1>>, index) -> (!fir.ref<!fir.char<1>>, !fir.ref<!fir.char<1>>)
 ! CHECK:           cf.br ^bb1
 ! CHECK:         ^bb1:
-! CHECK:           hlfir.assign %{{.*}} to %[[VAL_6]]#0 : !fir.ref<!fir.char<1>>, !fir.boxchar<1>
-! CHECK:           %[[VAL_10:.*]] = fir.emboxchar %[[VAL_6]]#1, %[[VAL_5]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+! CHECK:           hlfir.assign %{{.*}} to %[[VAL_6]]#0 : !fir.ref<!fir.char<1>>, !fir.ref<!fir.char<1>>
+! CHECK:           %[[VAL_10:.*]] = fir.emboxchar %[[VAL_6]]#1, %[[VAL_5]] : (!fir.ref<!fir.char<1>>, index) -> !fir.boxchar<1>
 ! CHECK:           return %[[VAL_10]] : !fir.boxchar<1>
 ! CHECK:         }
 
@@ -44,15 +43,14 @@ function foo2()
 ! CHECK-LABEL:   func.func @_QPfoo2(
 ! CHECK-SAME:                       %[[VAL_0:.*]]: !fir.ref<!fir.char<1>>,
 ! CHECK-SAME:                       %[[VAL_1:.*]]: index) -> !fir.boxchar<1> {
-! CHECK:           %[[VAL_2:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<!fir.char<1>>) -> !fir.ref<!fir.char<1,?>>
 ! CHECK:           %[[VAL_3:.*]] = arith.constant 1 : index
-! CHECK:           %[[VAL_4:.*]]:2 = hlfir.declare %[[VAL_2]] typeparams %[[VAL_3]] {uniq_name = "_QFfoo2Efoo2"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
+! CHECK:           %[[VAL_4:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_3]] {uniq_name = "_QFfoo2Efoo2"} : (!fir.ref<!fir.char<1>>, index) -> (!fir.ref<!fir.char<1>>, !fir.ref<!fir.char<1>>)
 ! CHECK:           %[[VAL_5:.*]] = arith.constant 1 : index
-! CHECK:           %[[VAL_6:.*]]:2 = hlfir.declare %[[VAL_2]] typeparams %[[VAL_5]] {uniq_name = "_QFfoo2Ebar2"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
+! CHECK:           %[[VAL_6:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_5]] {uniq_name = "_QFfoo2Ebar2"} : (!fir.ref<!fir.char<1>>, index) -> (!fir.ref<!fir.char<1>>, !fir.ref<!fir.char<1>>)
 ! CHECK:           cf.br ^bb1
 ! CHECK:         ^bb1:
-! CHECK:           hlfir.assign %{{.*}} to %[[VAL_6]]#0 : !fir.ref<!fir.char<1>>, !fir.boxchar<1>
-! CHECK:           %[[VAL_10:.*]] = fir.emboxchar %[[VAL_4]]#1, %[[VAL_3]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+! CHECK:           hlfir.assign %{{.*}} to %[[VAL_6]]#0 : !fir.ref<!fir.char<1>>, !fir.ref<!fir.char<1>>
+! CHECK:           %[[VAL_10:.*]] = fir.emboxchar %[[VAL_4]]#1, %[[VAL_3]] : (!fir.ref<!fir.char<1>>, index) -> !fir.boxchar<1>
 ! CHECK:           return %[[VAL_10]] : !fir.boxchar<1>
 ! CHECK:         }
 

flang/test/Lower/HLFIR/calls-assumed-shape.f90

@@ -90,8 +90,8 @@ subroutine takes_assumed_character(x)
 end subroutine
 ! CHECK-LABEL: func.func @_QPtest_explicit_char_to_box(
 ! CHECK:  %[[VAL_1:.*]]:2 = fir.unboxchar %[[VAL_0]] : (!fir.boxchar<1>) -> (!fir.ref<!fir.char<1,?>>, index)
-! CHECK:  %[[VAL_2:.*]] = arith.constant 10 : index
 ! CHECK:  %[[VAL_3:.*]] = fir.convert %[[VAL_1]]#0 : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<!fir.array<20x!fir.char<1,10>>>
+! CHECK:  %[[VAL_2:.*]] = arith.constant 10 : index
 ! CHECK:  %[[VAL_4:.*]] = arith.constant 20 : index
 ! CHECK:  %[[VAL_5:.*]] = fir.shape %[[VAL_4]] : (index) -> !fir.shape<1>
 ! CHECK:  %[[VAL_6:.*]]:2 = hlfir.declare %[[VAL_3]](%[[VAL_5:[a-z0-9]*]]) typeparams %[[VAL_2:[a-z0-9]*]] {uniq_name = "_QFtest_explicit_char_to_boxEe"} : (!fir.ref<!fir.array<20x!fir.char<1,10>>>, !fir.shape<1>, index) -> (!fir.ref<!fir.array<20x!fir.char<1,10>>>, !fir.ref<!fir.array<20x!fir.char<1,10>>>)

flang/test/Lower/HLFIR/char_extremum.f03

@@ -45,14 +45,14 @@ subroutine max2(c1, c2, c3)
 ! CHECK:  %[[VAL_2:[a-zA-Z0-9_]*]]  = fir.shape %[[VAL_C100]] : (index) -> !fir.shape<1>
 ! CHECK:  %[[VAL_3:[a-zA-Z0-9_]*]]:2 = hlfir.declare %[[VAL_1]](%[[VAL_2]]) typeparams %[[VAL_0]]#1 {{.*}} : (!fir.ref<!fir.array<100x!fir.char<1,?>>>, !fir.shape<1>, index) -> (!fir.box<!fir.array<100x!fir.char<1,?>>>, !fir.ref<!fir.array<100x!fir.char<1,?>>>)
 ! CHECK:  %[[VAL_4:[a-zA-Z0-9_]*]]:2 = fir.unboxchar %{{.*}} : (!fir.boxchar<1>) -> (!fir.ref<!fir.char<1,?>>, index)
-! CHECK:  %[[VAL_C10:[a-zA-Z0-9_]*]] = arith.constant 10 : index
 ! CHECK:  %[[VAL_5:[a-zA-Z0-9_]*]] = fir.convert %[[VAL_4]]#0 : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<!fir.array<100x!fir.char<1,10>>>
+! CHECK:  %[[VAL_C10:[a-zA-Z0-9_]*]] = arith.constant 10 : index
 ! CHECK:  %[[VAL_C100_0:[a-zA-Z0-9_]*]] = arith.constant 100 : index
 ! CHECK:  %[[VAL_6:[a-zA-Z0-9_]*]] = fir.shape %[[VAL_C100_0]] : (index) -> !fir.shape<1>
 ! CHECK:  %[[VAL_7:[a-zA-Z0-9_]*]]:2 = hlfir.declare %[[VAL_5]](%[[VAL_6]]) typeparams %[[VAL_C10]] {{.*}} : (!fir.ref<!fir.array<100x!fir.char<1,10>>>, !fir.shape<1>, index) -> (!fir.ref<!fir.array<100x!fir.char<1,10>>>, !fir.ref<!fir.array<100x!fir.char<1,10>>>)
 ! CHECK:  %[[VAL_8:[a-zA-Z0-9_]*]]:2 = fir.unboxchar %{{.*}} : (!fir.boxchar<1>) -> (!fir.ref<!fir.char<1,?>>, index)
-! CHECK:  %[[VAL_C20:[a-zA-Z0-9_]*]] = arith.constant 20 : index
 ! CHECK:  %[[VAL_9:[a-zA-Z0-9_]*]] = fir.convert %[[VAL_8]]#0 : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<!fir.array<100x!fir.char<1,20>>>
+! CHECK:  %[[VAL_C20:[a-zA-Z0-9_]*]] = arith.constant 20 : index
 ! CHECK:  %[[VAL_C100_1:[a-zA-Z0-9_]*]] = arith.constant 100 : index
 ! CHECK:  %[[VAL_10:[a-zA-Z0-9_]*]] = fir.shape %[[VAL_C100_1]] : (index) -> !fir.shape<1>
 ! CHECK:  %[[VAL_11:[a-zA-Z0-9_]*]]:2 = hlfir.declare %[[VAL_9]](%[[VAL_10]]) typeparams %[[VAL_C20]] {{.*}} : (!fir.ref<!fir.array<100x!fir.char<1,20>>>, !fir.shape<1>, index) -> (!fir.ref<!fir.array<100x!fir.char<1,20>>>, !fir.ref<!fir.array<100x!fir.char<1,20>>>)
@@ -78,14 +78,14 @@ subroutine min2(c1, c2, c3)
 ! CHECK:  %[[VAL_2:[a-zA-Z0-9_]*]] = fir.shape %[[VAL_C100]] : (index) -> !fir.shape<1>
 ! CHECK:  %[[VAL_3:[a-zA-Z0-9_]*]]:2 = hlfir.declare %[[VAL_1]](%[[VAL_2]]) typeparams %[[VAL_0]]#1 {{.*}} : (!fir.ref<!fir.array<100x!fir.char<1,?>>>, !fir.shape<1>, index) -> (!fir.box<!fir.array<100x!fir.char<1,?>>>, !fir.ref<!fir.array<100x!fir.char<1,?>>>)
 ! CHECK:  %[[VAL_4:[a-zA-Z0-9_]*]]:2 = fir.unboxchar %arg1 : (!fir.boxchar<1>) -> (!fir.ref<!fir.char<1,?>>, index)
-! CHECK:  %[[VAL_C10:[a-zA-Z0-9_]*]] = arith.constant 10 : index
 ! CHECK:  %[[VAL_5:[a-zA-Z0-9_]*]] = fir.convert %[[VAL_4]]#0 : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<!fir.array<100x!fir.char<1,10>>>
+! CHECK:  %[[VAL_C10:[a-zA-Z0-9_]*]] = arith.constant 10 : index
 ! CHECK:  %[[VAL_C100_0:[a-zA-Z0-9_]*]] = arith.constant 100 : index
 ! CHECK:  %[[VAL_6:[a-zA-Z0-9_]*]] = fir.shape %[[VAL_C100_0]] : (index) -> !fir.shape<1>
 ! CHECK:  %[[VAL_7:[a-zA-Z0-9_]*]]:2 = hlfir.declare %[[VAL_5]](%[[VAL_6]]) typeparams %[[VAL_C10]] {{.*}} : (!fir.ref<!fir.array<100x!fir.char<1,10>>>, !fir.shape<1>, index) -> (!fir.ref<!fir.array<100x!fir.char<1,10>>>, !fir.ref<!fir.array<100x!fir.char<1,10>>>)
 ! CHECK:  %[[VAL_8:[a-zA-Z0-9_]*]]:2 = fir.unboxchar %arg2 : (!fir.boxchar<1>) -> (!fir.ref<!fir.char<1,?>>, index)
-! CHECK:  %[[VAL_C20:[a-zA-Z0-9_]*]] = arith.constant 20 : index
 ! CHECK:  %[[VAL_C9:[a-zA-Z0-9_]*]] = fir.convert %[[VAL_8]]#0 : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<!fir.array<100x!fir.char<1,20>>>
+! CHECK:  %[[VAL_C20:[a-zA-Z0-9_]*]] = arith.constant 20 : index
 ! CHECK:  %[[VAL_C100_1:[a-zA-Z0-9_]*]] = arith.constant 100 : index
 ! CHECK:  %[[VAL_10:[a-zA-Z0-9_]*]] = fir.shape %[[VAL_C100_1]] : (index) -> !fir.shape<1>
 ! CHECK:  %[[VAL_11:[a-zA-Z0-9_]*]]:2 = hlfir.declare %[[VAL_C9]](%[[VAL_10]]) typeparams %[[VAL_C20]] {{.*}} : (!fir.ref<!fir.array<100x!fir.char<1,20>>>, !fir.shape<1>, index) -> (!fir.ref<!fir.array<100x!fir.char<1,20>>>, !fir.ref<!fir.array<100x!fir.char<1,20>>>)

flang/test/Lower/HLFIR/convert-variable.f90

@@ -22,8 +22,8 @@ subroutine scalar_character_cst_len(c)
 ! CHECK-LABEL: func.func @_QPscalar_character_cst_len(
 ! CHECK-SAME:    %[[VAL_0:.*]]: !fir.boxchar<1>
 ! CHECK:  %[[VAL_1:.*]]:2 = fir.unboxchar %[[VAL_0]] : (!fir.boxchar<1>) -> (!fir.ref<!fir.char<1,?>>, index)
-! CHECK:  %[[VAL_2:.*]] = arith.constant 10 : index
 ! CHECK:  %[[VAL_3:.*]] = fir.convert %[[VAL_1]]#0 : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<!fir.char<1,10>>
+! CHECK:  %[[VAL_2:.*]] = arith.constant 10 : index
 ! CHECK:  %[[VAL_4:.*]] = hlfir.declare %[[VAL_3]] typeparams %[[VAL_2]] {uniq_name = "_QFscalar_character_cst_lenEc"} : (!fir.ref<!fir.char<1,10>>, index) -> (!fir.ref<!fir.char<1,10>>, !fir.ref<!fir.char<1,10>>)
 
 subroutine array_numeric(x)

flang/test/Lower/HLFIR/function-return.f90

@@ -17,10 +17,9 @@ integer function simple_return()
 end function
 ! CHECK-LABEL: func.func @_QPchar_return(
 ! CHECK-SAME:  %[[VAL_0:.*]]: !fir.ref<!fir.char<1,10>>
-! CHECK:  %[[VAL_2:.*]] = fir.convert %[[VAL_0]] : (!fir.ref<!fir.char<1,10>>) -> !fir.ref<!fir.char<1,?>>
 ! CHECK:  %[[VAL_3:.*]] = arith.constant 10 : index
-! CHECK:  %[[VAL_4:.*]]:2 = hlfir.declare %[[VAL_2]] typeparams %[[VAL_3]] {uniq_name = "_QFchar_returnEchar_return"} : (!fir.ref<!fir.char<1,?>>, index) -> (!fir.boxchar<1>, !fir.ref<!fir.char<1,?>>)
-! CHECK:  %[[VAL_8:.*]] = fir.emboxchar %[[VAL_4]]#1, %[[VAL_3]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+! CHECK:  %[[VAL_4:.*]]:2 = hlfir.declare %[[VAL_0]] typeparams %[[VAL_3]] {uniq_name = "_QFchar_returnEchar_return"} : (!fir.ref<!fir.char<1,10>>, index) -> (!fir.ref<!fir.char<1,10>>, !fir.ref<!fir.char<1,10>>)
+! CHECK:  %[[VAL_8:.*]] = fir.emboxchar %[[VAL_4]]#1, %[[VAL_3]] : (!fir.ref<!fir.char<1,10>>, index) -> !fir.boxchar<1>
 ! CHECK:  return %[[VAL_8]] : !fir.boxchar<1>
 
 integer function array_return()

flang/test/Lower/HLFIR/structure-constructor.f90

@@ -41,8 +41,8 @@ end subroutine test1
 ! CHECK:           %[[VAL_2:.*]] = fir.alloca !fir.type<_QMtypesTt1{c:!fir.char<1,4>}> {bindc_name = "res", uniq_name = "_QFtest1Eres"}
 ! CHECK:           %[[VAL_3:.*]]:2 = hlfir.declare %[[VAL_2]] {uniq_name = "_QFtest1Eres"} : (!fir.ref<!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>) -> (!fir.ref<!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>, !fir.ref<!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>)
 ! CHECK:           %[[VAL_4:.*]]:2 = fir.unboxchar %[[VAL_0]] : (!fir.boxchar<1>) -> (!fir.ref<!fir.char<1,?>>, index)
-! CHECK:           %[[VAL_5:.*]] = arith.constant 4 : index
 ! CHECK:           %[[VAL_6:.*]] = fir.convert %[[VAL_4]]#0 : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<!fir.char<1,4>>
+! CHECK:           %[[VAL_5:.*]] = arith.constant 4 : index
 ! CHECK:           %[[VAL_7:.*]]:2 = hlfir.declare %[[VAL_6]] typeparams %[[VAL_5]] {uniq_name = "_QFtest1Ex"} : (!fir.ref<!fir.char<1,4>>, index) -> (!fir.ref<!fir.char<1,4>>, !fir.ref<!fir.char<1,4>>)
 ! CHECK:           %[[VAL_8:.*]]:2 = hlfir.declare %[[VAL_1]] {uniq_name = "ctor.temp"} : (!fir.ref<!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>) -> (!fir.ref<!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>, !fir.ref<!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>)
 ! CHECK:           %[[VAL_9:.*]] = fir.embox %[[VAL_8]]#0 : (!fir.ref<!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>) -> !fir.box<!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>
@@ -220,8 +220,8 @@ end subroutine test6
 ! CHECK:           %[[VAL_5:.*]] = fir.alloca !fir.type<_QMtypesTt5{t5m:!fir.box<!fir.heap<!fir.array<?x!fir.type<_QMtypesTt4{c:!fir.box<!fir.heap<!fir.array<?x!fir.char<1,2>>>>}>>>>}>
 ! CHECK:           %[[VAL_6:.*]] = fir.alloca !fir.type<_QMtypesTt6{t5m:!fir.box<!fir.heap<!fir.array<?x!fir.type<_QMtypesTt4{c:!fir.box<!fir.heap<!fir.array<?x!fir.char<1,2>>>>}>>>>,t6m:!fir.array<1x!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>}>
 ! CHECK:           %[[VAL_7:.*]]:2 = fir.unboxchar %[[VAL_1]] : (!fir.boxchar<1>) -> (!fir.ref<!fir.char<1,?>>, index)
-! CHECK:           %[[VAL_8:.*]] = arith.constant 4 : index
 ! CHECK:           %[[VAL_9:.*]] = fir.convert %[[VAL_7]]#0 : (!fir.ref<!fir.char<1,?>>) -> !fir.ref<!fir.char<1,4>>
+! CHECK:           %[[VAL_8:.*]] = arith.constant 4 : index
 ! CHECK:           %[[VAL_10:.*]]:2 = hlfir.declare %[[VAL_9]] typeparams %[[VAL_8]] {uniq_name = "_QFtest6Ec"} : (!fir.ref<!fir.char<1,4>>, index) -> (!fir.ref<!fir.char<1,4>>, !fir.ref<!fir.char<1,4>>)
 ! CHECK:           %[[VAL_11:.*]] = fir.alloca !fir.type<_QMtypesTt6{t5m:!fir.box<!fir.heap<!fir.array<?x!fir.type<_QMtypesTt4{c:!fir.box<!fir.heap<!fir.array<?x!fir.char<1,2>>>>}>>>>,t6m:!fir.array<1x!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>}> {bindc_name = "res", uniq_name = "_QFtest6Eres"}
 ! CHECK:           %[[VAL_12:.*]]:2 = hlfir.declare %[[VAL_11]] {uniq_name = "_QFtest6Eres"} : (!fir.ref<!fir.type<_QMtypesTt6{t5m:!fir.box<!fir.heap<!fir.array<?x!fir.type<_QMtypesTt4{c:!fir.box<!fir.heap<!fir.array<?x!fir.char<1,2>>>>}>>>>,t6m:!fir.array<1x!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>}>>) -> (!fir.ref<!fir.type<_QMtypesTt6{t5m:!fir.box<!fir.heap<!fir.array<?x!fir.type<_QMtypesTt4{c:!fir.box<!fir.heap<!fir.array<?x!fir.char<1,2>>>>}>>>>,t6m:!fir.array<1x!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>}>>, !fir.ref<!fir.type<_QMtypesTt6{t5m:!fir.box<!fir.heap<!fir.array<?x!fir.type<_QMtypesTt4{c:!fir.box<!fir.heap<!fir.array<?x!fir.char<1,2>>>>}>>>>,t6m:!fir.array<1x!fir.type<_QMtypesTt1{c:!fir.char<1,4>}>>}>>)

flang/test/Lower/Intrinsics/merge.f90

@@ -14,7 +14,7 @@ function merge_test(o1, o2, mask)
 ! CHECK: %[[a2:.*]] = fir.load %[[arg4]] : !fir.ref<!fir.logical<4>>
 ! CHECK: %[[a3:.*]] = fir.convert %[[a2]] : (!fir.logical<4>) -> i1
 ! CHECK: %[[a4:.*]] = arith.select %[[a3]], %[[a0_cast]], %[[a1_cast]] : !fir.ref<!fir.char<1>>
-! CHECK:  %{{.*}} = fir.convert %[[a4]] : (!fir.ref<!fir.char<1>>) -> !fir.ref<i8>
+! CHECK:  %{{.*}} = fir.load %[[a4]] : !fir.ref<!fir.char<1>>
 end
 
 ! CHECK-LABEL: func @_QPmerge_test2(

flang/test/Lower/OpenMP/FIR/copyin.f90

@@ -85,8 +85,7 @@ subroutine copyin_scalar_array()
 ! CHECK:           }
 ! CHECK:           fir.array_merge_store %[[VAL_16]], %[[VAL_35:.*]] to %[[VAL_14]] : !fir.array<10x!fir.char<1,5>>, !fir.array<10x!fir.char<1,5>>, !fir.ref<!fir.array<10x!fir.char<1,5>>>
 ! CHECK:           omp.barrier
-! CHECK:           %[[VAL_36:.*]] = fir.convert %[[VAL_7]] : (!fir.ref<!fir.char<1,5>>) -> !fir.ref<!fir.char<1,?>>
-! CHECK:           %[[VAL_37:.*]] = fir.emboxchar %[[VAL_36]], %[[VAL_1]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+! CHECK:           %[[VAL_37:.*]] = fir.emboxchar %[[VAL_7]], %[[VAL_1]] : (!fir.ref<!fir.char<1,5>>, index) -> !fir.boxchar<1>
 ! CHECK:           %[[VAL_38:.*]] = fir.convert %[[VAL_14]] : (!fir.ref<!fir.array<10x!fir.char<1,5>>>) -> !fir.ref<!fir.char<1,?>>
 ! CHECK:           %[[VAL_39:.*]] = fir.emboxchar %[[VAL_38]], %[[VAL_4]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
 ! CHECK:           fir.call @_QPsub2(%[[VAL_37]], %[[VAL_39]]) {{.*}}: (!fir.boxchar<1>, !fir.boxchar<1>) -> ()

flang/test/Lower/OpenMP/FIR/private-commonblock.f90

@@ -34,8 +34,7 @@ subroutine private_common
 !CHECK: %[[val_11:.*]] = fir.coordinate_of %[[val_10]], %[[val_c49]] : (!fir.ref<!fir.array<?xi8>>, index) -> !fir.ref<i8>
 !CHECK: %[[val_12:.*]] = fir.convert %[[val_11]] : (!fir.ref<i8>) -> !fir.ref<!fir.array<5x!fir.char<1,5>>>
 !CHECK: %[[val_c5_0:.*]] = arith.constant 5 : index
-!CHECK: %[[val_13:.*]] = fir.convert %[[val_9]] : (!fir.ref<!fir.char<1,5>>) -> !fir.ref<!fir.char<1,?>>
-!CHECK: %[[val_14:.*]] = fir.emboxchar %[[val_13]], %[[val_c5]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+!CHECK: %[[val_14:.*]] = fir.emboxchar %[[val_9]], %[[val_c5]] : (!fir.ref<!fir.char<1,5>>, index) -> !fir.boxchar<1>
 !CHECK: %[[val_15:.*]] = fir.convert %[[val_12]] : (!fir.ref<!fir.array<5x!fir.char<1,5>>>) -> !fir.ref<!fir.char<1,?>>
 !CHECK: %[[val_16:.*]] = fir.emboxchar %[[val_15]], %[[val_c5_0]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
 !CHECK: fir.call @_QPsub1(%[[val_3]], %[[val_6]], %[[val_14]], %[[val_16]]) fastmath<contract> : (!fir.ref<i32>, !fir.ref<!fir.array<10xf32>>, !fir.boxchar<1>, !fir.boxchar<1>) -> ()
@@ -44,15 +43,13 @@ subroutine private_common
 !CHECK: %[[val_22:.*]] = fir.alloca !fir.array<10xf32> {bindc_name = "b", pinned, uniq_name = "_QFprivate_clause_commonblockEb"}
 !CHECK: %[[val_23:.*]] = fir.alloca !fir.char<1,5> {bindc_name = "c", pinned, uniq_name = "_QFprivate_clause_commonblockEc"}
 !CHECK: %[[val_24:.*]] = fir.alloca !fir.array<5x!fir.char<1,5>> {bindc_name = "d", pinned, uniq_name = "_QFprivate_clause_commonblockEd"}
-!CHECK: %[[val_25:.*]] = fir.convert %[[val_23]] : (!fir.ref<!fir.char<1,5>>) -> !fir.ref<!fir.char<1,?>>
-!CHECK: %[[val_26:.*]] = fir.emboxchar %[[val_25]], %[[val_c5]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+!CHECK: %[[val_26:.*]] = fir.emboxchar %[[val_23]], %[[val_c5]] : (!fir.ref<!fir.char<1,5>>, index) -> !fir.boxchar<1>
 !CHECK: %[[val_27:.*]] = fir.convert %[[val_24]] : (!fir.ref<!fir.array<5x!fir.char<1,5>>>) -> !fir.ref<!fir.char<1,?>>
 !CHECK: %[[val_28:.*]] = fir.emboxchar %[[val_27]], %[[val_c5_0]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
 !CHECK: fir.call @_QPsub2(%[[val_21]], %[[val_22]], %[[val_26]], %[[val_28]]) fastmath<contract> : (!fir.ref<i32>, !fir.ref<!fir.array<10xf32>>, !fir.boxchar<1>, !fir.boxchar<1>) -> ()
 !CHECK: omp.terminator
 !CHECK: }
-!CHECK: %[[val_17:.*]] = fir.convert %[[val_9]] : (!fir.ref<!fir.char<1,5>>) -> !fir.ref<!fir.char<1,?>>
-!CHECK: %[[val_18:.*]] = fir.emboxchar %[[val_17]], %[[val_c5]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
+!CHECK: %[[val_18:.*]] = fir.emboxchar %[[val_9]], %[[val_c5]] : (!fir.ref<!fir.char<1,5>>, index) -> !fir.boxchar<1>
 !CHECK: %[[val_19:.*]] = fir.convert %[[val_12]] : (!fir.ref<!fir.array<5x!fir.char<1,5>>>) -> !fir.ref<!fir.char<1,?>>
 !CHECK: %[[val_20:.*]] = fir.emboxchar %[[val_19]], %[[val_c5_0]] : (!fir.ref<!fir.char<1,?>>, index) -> !fir.boxchar<1>
 !CHECK: fir.call @_QPsub3(%[[val_3]], %[[val_6]], %[[val_18]], %[[val_20]]) fastmath<contract> : {{.*}}