[flang] Detect fir.class nested in fir.box as invalid element type

[clementval]

Summary

Catch invalid element type in fir.box in the verifier so
it does not propagate later in lowering.

[PeteSteinfeld]

When I build and test this patch, I get errors:

Failed Tests (2):
  Flang :: Lower/HLFIR/allocatables-and-pointers.f90
  Flang :: Lower/Intrinsics/associated.f90

Let me know if you need more detail on the failures.

[clementval]

In D146078#4194285, @PeteSteinfeld wrote:

When I build and test this patch, I get errors:

Failed Tests (2):
  Flang :: Lower/HLFIR/allocatables-and-pointers.f90
  Flang :: Lower/Intrinsics/associated.f90

Let me know if you need more detail on the failures.

The dependency was wrong. I updated it and it should be fine now.

[PeteSteinfeld]

I'm still getting the same failures.

[clementval]

Rebase

[clementval]

Something was probably messed up with the dependency. I rebased this patch now that the other has landed.

[clementval]

Rebase on D146120

[PeteSteinfeld]

All builds and tests correctly and looks good.

flang/lib/Optimizer/Dialect/FIRType.cpp

 
 //===----------------------------------------------------------------------===//
 // BoxType
 //===----------------------------------------------------------------------===//
 
 mlir::LogicalResult
 fir::BoxType::verify(llvm::function_ref<mlir::InFlightDiagnostic()> emitError,
                      mlir::Type eleTy) {
+  if (eleTy.isa<fir::BaseBoxType>())
+    return emitError() << "invalid element type\n";
   // TODO
   return mlir::success();
 }
 
 //===----------------------------------------------------------------------===//
 // BoxCharType
 //===----------------------------------------------------------------------===//
 

flang/test/Fir/invalid-types.fir

 
 // expected-error@+1 {{expected non-function type}}
 func.func private @oth3() -> !fir.vector<10:>
 
 // -----
 
 // expected-error@+1 {{invalid element type}}
 func.func private @upe() -> !fir.class<!fir.box<i32>>
+
+// -----
+
+// expected-error@+1 {{invalid element type}}
+func.func private @upe() -> !fir.box<!fir.class<none>>