Return null expr when a negative array was created.

Fix #69198

Author: lwshanbd

clang/lib/AST/Expr.cpp

@@ -4983,10 +4983,10 @@ QualType OMPArraySectionExpr::getBaseOriginalType(const Expr *Base) {
   for (unsigned Cnt = 0; Cnt < ArraySectionCount; ++Cnt) {
     if (OriginalTy->isAnyPointerType())
       OriginalTy = OriginalTy->getPointeeType();
-    else {
-      assert (OriginalTy->isArrayType());
+    else if (OriginalTy->isArrayType())
       OriginalTy = OriginalTy->castAsArrayTypeUnsafe()->getElementType();
-    }
+    else
+      return {};
   }
   return OriginalTy;
 }

clang/lib/Sema/SemaOpenMP.cpp

@@ -21014,6 +21014,8 @@ Sema::ActOnOpenMPDependClause(const OMPDependClause::DependDataTy &Data,
           if (OASE) {
             QualType BaseType =
                 OMPArraySectionExpr::getBaseOriginalType(OASE->getBase());
+            if (BaseType.isNull())
+              return nullptr;
             if (const auto *ATy = BaseType->getAsArrayTypeUnsafe())
               ExprTy = ATy->getElementType();
             else

clang/test/OpenMP/bug69198.c

@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -verify -fopenmp -x c -triple x86_64-apple-darwin10 %s
+// expected-no-diagnostics
+
+int c[-1];
+
+void foo (){
+  #pragma omp task depend(inout: c[:][:])
+}