[SYCL] Do not crash on attempt to visit invalid decl (#2411)

Author: Fznamznon

clang/lib/Sema/SemaSYCL.cpp

@@ -2481,6 +2481,10 @@ void Sema::CheckSYCLKernelCall(FunctionDecl *KernelFunc, SourceRange CallLoc,
       Diag(KernelFunc->getLocation(), diag::warn_sycl_pass_by_value_deprecated);
   }
 
+  // Do not visit invalid kernel object.
+  if (KernelObj->isInvalidDecl())
+    return;
+
   KernelObjVisitor Visitor{*this};
   DiagnosingSYCLKernel = true;
   Visitor.VisitRecordBases(KernelObj, FieldChecker, UnionChecker,
@@ -2520,6 +2524,10 @@ void Sema::ConstructOpenCLKernel(FunctionDecl *KernelCallerFunc,
   const CXXRecordDecl *KernelObj = getKernelObjectType(KernelCallerFunc);
   assert(KernelObj && "invalid kernel caller");
 
+  // Do not visit invalid kernel object.
+  if (KernelObj->isInvalidDecl())
+    return;
+
   // Calculate both names, since Integration headers need both.
   std::string CalculatedName, StableName;
   std::tie(CalculatedName, StableName) =

clang/test/SemaSYCL/invalid-kernel-arguments.cpp

@@ -0,0 +1,70 @@
+// RUN: %clang_cc1 -I %S/Inputs -fsycl -fsycl-is-device -fsyntax-only -Wno-sycl-2017-compat -verify %s
+
+// This test checks that compiler doesn't crash if type of kernel argument is
+// invalid.
+
+#include <sycl.hpp>
+
+// Invalid field -> invalid decl
+class A {
+public:
+  // expected-error@+1 {{unknown type name 'it'}}
+  it KN;
+};
+
+// Invalid type of field -> invalid decl
+class B {
+  A Arr[100];
+};
+
+// Invalid base -> invalid decl
+class E : public B {
+};
+
+// expected-note@+1 {{forward declaration of 'C'}}
+class C;
+
+// Invalid base -> invalid decl
+// expected-error@+1 {{base class has incomplete type}}
+class D : public B, C {
+};
+
+// Such thing is also invalid and caused crash
+// expected-note@+1 {{definition of 'F' is not complete until the closing '}'}}
+class F {
+  // expected-error@+1 {{field has incomplete type 'F'}}
+  F Self;
+};
+
+template <typename T>
+class G {
+  T Field;
+};
+
+class H {
+  // expected-note@+1 {{previous declaration is here}}
+  int A;
+  // expected-error@+1 {{duplicate member 'A'}}
+  int A;
+};
+
+int main() {
+  A Obj{};
+  D Obj1{};
+  B Obj2{};
+  E Obj3{};
+  F Obj4{};
+  G<A> Obj5{};
+  H Obj6{};
+  cl::sycl::kernel_single_task<class kernel>(
+      [=]() {
+        (void)Obj;
+        (void)Obj1;
+        (void)Obj2;
+        (void)Obj3;
+        (void)Obj4;
+        (void)Obj5;
+        (void)Obj6;
+      });
+  return 0;
+}