[Clang][OpenMP] Fix `!isNull() && "Cannot retrieve a NULL type pointer"' fail. (llvm#81015)

Fixes : llvm#69085 , llvm#69200

**PR SUMMARY**: "Added Null check for negative sized array and a test
for the same"

Author: Sh0g0-1758

clang/lib/Sema/SemaOpenMP.cpp

@@ -21124,6 +21124,8 @@ Sema::ActOnOpenMPDependClause(const OMPDependClause::DependDataTy &Data,
               ExprTy = ATy->getElementType();
             else
               ExprTy = BaseType->getPointeeType();
+            if (BaseType.isNull() || ExprTy.isNull())
+              return nullptr;
             ExprTy = ExprTy.getNonReferenceType();
             const Expr *Length = OASE->getLength();
             Expr::EvalResult Result;

clang/test/OpenMP/bug69085.c

@@ -0,0 +1,10 @@
+// RUN: %clang_cc1 -verify -O0 -fopenmp-simd %s
+
+int k[-1]; // expected-error {{'k' declared as an array with a negative size}}
+
+void foo() {
+    #pragma omp task depend(inout: k [:])
+    {
+        k[0] = 1;
+    }
+}