[clang] [Clang] FunctionEffects: Correctly navigate through array types in FunctionEffectsRef::get(). (PR #121525)

[Doug Wyatt via cfe-commits]

================
@@ -8836,13 +8836,22 @@ void FixedPointValueToString(SmallVectorImpl<char> &Str, llvm::APSInt Val,
                              unsigned Scale);
 
 inline FunctionEffectsRef FunctionEffectsRef::get(QualType QT) {
+  const Type *TypePtr = QT.getTypePtr();
   while (true) {
-    QualType Pointee = QT->getPointeeType();
-    if (Pointee.isNull())
+    // Note that getPointeeType() seems to successfully navigate some constructs
+    // for which isAnyPointerType() returns false (e.g.
+    // pointer-to-member-function).
+    QualType Pointee = TypePtr->getPointeeType();
+    if (Pointee.isNull()) {
+      if (TypePtr->isArrayType()) {
+        TypePtr = TypePtr->getBaseElementTypeUnsafe();
+        continue;
+      }
       break;
-    QT = Pointee;
+    }
+    TypePtr = Pointee.getTypePtr();
   }
-  if (const auto *FPT = QT->getAs<FunctionProtoType>())
+  if (const auto *FPT = TypePtr->getAs<FunctionProtoType>())
----------------
dougsonos wrote:

```
inline bool Type::isAnyPointerType() const {
  return isPointerType() || isObjCObjectPointerType();
}

inline bool Type::isPointerType() const {
  return isa<PointerType>(CanonicalType);
}

inline bool Type::isMemberPointerType() const {
  return isa<MemberPointerType>(CanonicalType);
}

inline bool Type::isMemberFunctionPointerType() const {
  if (const auto *T = getAs<MemberPointerType>())
    return T->isMemberFunctionPointer();
  else
    return false;
}
```

https://github.com/llvm/llvm-project/pull/121525