flang/lib/Semantics/pointer-assignment.cpp

   1 //===-- lib/Semantics/pointer-assignment.cpp ------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "pointer-assignment.h"
  10 #include "definable.h"
  11 #include "flang/Common/idioms.h"
  12 #include "flang/Common/restorer.h"
  13 #include "flang/Common/template.h"
  14 #include "flang/Evaluate/characteristics.h"
  15 #include "flang/Evaluate/expression.h"
  16 #include "flang/Evaluate/fold.h"
  17 #include "flang/Evaluate/tools.h"
  18 #include "flang/Parser/message.h"
  19 #include "flang/Parser/parse-tree-visitor.h"
  20 #include "flang/Parser/parse-tree.h"
  21 #include "flang/Semantics/expression.h"
  22 #include "flang/Semantics/symbol.h"
  23 #include "flang/Semantics/tools.h"
  24 #include "llvm/Support/raw_ostream.h"
  25 #include <optional>
  26 #include <set>
  27 #include <string>
  28 #include <type_traits>
  29
  30 // Semantic checks for pointer assignment.
  31
  32 namespace Fortran::semantics {
  33
  34 using namespace parser::literals;
  35 using evaluate::characteristics::DummyDataObject;
  36 using evaluate::characteristics::FunctionResult;
  37 using evaluate::characteristics::Procedure;
  38 using evaluate::characteristics::TypeAndShape;
  39 using parser::MessageFixedText;
  40 using parser::MessageFormattedText;
  41
  42 class PointerAssignmentChecker {
  43 public:
  44   PointerAssignmentChecker(SemanticsContext &context, const Scope &scope,
  45       parser::CharBlock source, const std::string &description)
  46       : context_{context}, scope_{scope}, source_{source}, description_{
  47                                                                description} {}
  48   PointerAssignmentChecker(
  49       SemanticsContext &context, const Scope &scope, const Symbol &lhs)
  50       : context_{context}, scope_{scope}, source_{lhs.name()},
  51         description_{"pointer '"s + lhs.name().ToString() + '\''}, lhs_{&lhs} {
  52     set_lhsType(TypeAndShape::Characterize(lhs, foldingContext_));
  53     set_isContiguous(lhs.attrs().test(Attr::CONTIGUOUS));
  54     set_isVolatile(lhs.attrs().test(Attr::VOLATILE));
  55   }
  56   PointerAssignmentChecker &set_lhsType(std::optional<TypeAndShape> &&);
  57   PointerAssignmentChecker &set_isContiguous(bool);
  58   PointerAssignmentChecker &set_isVolatile(bool);
  59   PointerAssignmentChecker &set_isBoundsRemapping(bool);
  60   PointerAssignmentChecker &set_isAssumedRank(bool);
  61   PointerAssignmentChecker &set_pointerComponentLHS(const Symbol *);
  62   bool CheckLeftHandSide(const SomeExpr &);
  63   bool Check(const SomeExpr &);
  64
  65 private:
  66   bool CharacterizeProcedure();
  67   template <typename T> bool Check(const T &);
  68   template <typename T> bool Check(const evaluate::Expr<T> &);
  69   template <typename T> bool Check(const evaluate::FunctionRef<T> &);
  70   template <typename T> bool Check(const evaluate::Designator<T> &);
  71   bool Check(const evaluate::NullPointer &);
  72   bool Check(const evaluate::ProcedureDesignator &);
  73   bool Check(const evaluate::ProcedureRef &);
  74   // Target is a procedure
  75   bool Check(parser::CharBlock rhsName, bool isCall,
  76       const Procedure * = nullptr,
  77       const evaluate::SpecificIntrinsic *specific = nullptr);
  78   bool LhsOkForUnlimitedPoly() const;
  79   template <typename... A> parser::Message *Say(A &&...);
  80   template <typename FeatureOrUsageWarning, typename... A>
  81   parser::Message *Warn(FeatureOrUsageWarning, A &&...);
  82
  83   SemanticsContext &context_;
  84   evaluate::FoldingContext &foldingContext_{context_.foldingContext()};
  85   const Scope &scope_;
  86   const parser::CharBlock source_;
  87   const std::string description_;
  88   const Symbol *lhs_{nullptr};
  89   std::optional<TypeAndShape> lhsType_;
  90   std::optional<Procedure> procedure_;
  91   bool characterizedProcedure_{false};
  92   bool isContiguous_{false};
  93   bool isVolatile_{false};
  94   bool isBoundsRemapping_{false};
  95   bool isAssumedRank_{false};
  96   const Symbol *pointerComponentLHS_{nullptr};
  97 };
  98
  99 PointerAssignmentChecker &PointerAssignmentChecker::set_lhsType(
 100     std::optional<TypeAndShape> &&lhsType) {
 101   lhsType_ = std::move(lhsType);
 102   return *this;
 103 }
 104
 105 PointerAssignmentChecker &PointerAssignmentChecker::set_isContiguous(
 106     bool isContiguous) {
 107   isContiguous_ = isContiguous;
 108   return *this;
 109 }
 110
 111 PointerAssignmentChecker &PointerAssignmentChecker::set_isVolatile(
 112     bool isVolatile) {
 113   isVolatile_ = isVolatile;
 114   return *this;
 115 }
 116
 117 PointerAssignmentChecker &PointerAssignmentChecker::set_isBoundsRemapping(
 118     bool isBoundsRemapping) {
 119   isBoundsRemapping_ = isBoundsRemapping;
 120   return *this;
 121 }
 122
 123 PointerAssignmentChecker &PointerAssignmentChecker::set_isAssumedRank(
 124     bool isAssumedRank) {
 125   isAssumedRank_ = isAssumedRank;
 126   return *this;
 127 }
 128
 129 PointerAssignmentChecker &PointerAssignmentChecker::set_pointerComponentLHS(
 130     const Symbol *symbol) {
 131   pointerComponentLHS_ = symbol;
 132   return *this;
 133 }
 134
 135 bool PointerAssignmentChecker::CharacterizeProcedure() {
 136   if (!characterizedProcedure_) {
 137     characterizedProcedure_ = true;
 138     if (lhs_ && IsProcedure(*lhs_)) {
 139       procedure_ = Procedure::Characterize(*lhs_, foldingContext_);
 140     }
 141   }
 142   return procedure_.has_value();
 143 }
 144
 145 bool PointerAssignmentChecker::CheckLeftHandSide(const SomeExpr &lhs) {
 146   if (auto whyNot{WhyNotDefinable(foldingContext_.messages().at(), scope_,
 147           DefinabilityFlags{DefinabilityFlag::PointerDefinition}, lhs)}) {
 148     if (auto *msg{Say(
 149             "The left-hand side of a pointer assignment is not definable"_err_en_US)}) {
 150       msg->Attach(std::move(whyNot->set_severity(parser::Severity::Because)));
 151     }
 152     return false;
 153   } else if (evaluate::IsAssumedRank(lhs)) {
 154     Say("The left-hand side of a pointer assignment must not be an assumed-rank dummy argument"_err_en_US);
 155     return false;
 156   } else {
 157     return true;
 158   }
 159 }
 160
 161 template <typename T> bool PointerAssignmentChecker::Check(const T &) {
 162   // Catch-all case for really bad target expression
 163   Say("Target associated with %s must be a designator or a call to a"
 164       " pointer-valued function"_err_en_US,
 165       description_);
 166   return false;
 167 }
 168
 169 template <typename T>
 170 bool PointerAssignmentChecker::Check(const evaluate::Expr<T> &x) {
 171   return common::visit([&](const auto &x) { return Check(x); }, x.u);
 172 }
 173
 174 bool PointerAssignmentChecker::Check(const SomeExpr &rhs) {
 175   if (HasVectorSubscript(rhs)) { // C1025
 176     Say("An array section with a vector subscript may not be a pointer target"_err_en_US);
 177     return false;
 178   }
 179   if (ExtractCoarrayRef(rhs)) { // C1026
 180     Say("A coindexed object may not be a pointer target"_err_en_US);
 181     return false;
 182   }
 183   if (!common::visit([&](const auto &x) { return Check(x); }, rhs.u)) {
 184     return false;
 185   }
 186   if (IsNullPointer(rhs)) {
 187     return true;
 188   }
 189   if (lhs_ && IsProcedure(*lhs_)) {
 190     return true;
 191   }
 192   if (const auto *pureProc{FindPureProcedureContaining(scope_)}) {
 193     if (pointerComponentLHS_) { // C1594(4) is a hard error
 194       if (const Symbol * object{FindExternallyVisibleObject(rhs, *pureProc)}) {
 195         if (auto *msg{Say(
 196                 "Externally visible object '%s' may not be associated with pointer component '%s' in a pure procedure"_err_en_US,
 197                 object->name(), pointerComponentLHS_->name())}) {
 198           msg->Attach(object->name(), "Object declaration"_en_US)
 199               .Attach(
 200                   pointerComponentLHS_->name(), "Pointer declaration"_en_US);
 201         }
 202         return false;
 203       }
 204     } else if (const Symbol * base{GetFirstSymbol(rhs)}) {
 205       if (const char *why{WhyBaseObjectIsSuspicious(
 206               base->GetUltimate(), scope_)}) { // C1594(3)
 207         evaluate::SayWithDeclaration(foldingContext_.messages(), *base,
 208             "A pure subprogram may not use '%s' as the target of pointer assignment because it is %s"_err_en_US,
 209             base->name(), why);
 210         return false;
 211       }
 212     }
 213   }
 214   if (isContiguous_) {
 215     if (auto contiguous{evaluate::IsContiguous(rhs, foldingContext_)}) {
 216       if (!*contiguous) {
 217         Say("CONTIGUOUS pointer may not be associated with a discontiguous target"_err_en_US);
 218         return false;
 219       }
 220     } else {
 221       Warn(common::UsageWarning::PointerToPossibleNoncontiguous,
 222           "Target of CONTIGUOUS pointer association is not known to be contiguous"_warn_en_US);
 223     }
 224   }
 225   // Warn about undefinable data targets
 226   if (auto because{
 227           WhyNotDefinable(foldingContext_.messages().at(), scope_, {}, rhs)}) {
 228     if (auto *msg{Warn(common::UsageWarning::PointerToUndefinable,
 229             "Pointer target is not a definable variable"_warn_en_US)}) {
 230       msg->Attach(std::move(because->set_severity(parser::Severity::Because)));
 231       return false;
 232     }
 233   }
 234   return true;
 235 }
 236
 237 bool PointerAssignmentChecker::Check(const evaluate::NullPointer &) {
 238   return true; // P => NULL() without MOLD=; always OK
 239 }
 240
 241 template <typename T>
 242 bool PointerAssignmentChecker::Check(const evaluate::FunctionRef<T> &f) {
 243   std::string funcName;
 244   const auto *symbol{f.proc().GetSymbol()};
 245   if (symbol) {
 246     funcName = symbol->name().ToString();
 247   } else if (const auto *intrinsic{f.proc().GetSpecificIntrinsic()}) {
 248     funcName = intrinsic->name;
 249   }
 250   auto proc{
 251       Procedure::Characterize(f.proc(), foldingContext_, /*emitError=*/true)};
 252   if (!proc) {
 253     return false;
 254   }
 255   std::optional<MessageFixedText> msg;
 256   const auto &funcResult{proc->functionResult}; // C1025
 257   if (!funcResult) {
 258     msg = "%s is associated with the non-existent result of reference to"
 259           " procedure"_err_en_US;
 260   } else if (CharacterizeProcedure()) {
 261     // Shouldn't be here in this function unless lhs is an object pointer.
 262     msg = "Procedure %s is associated with the result of a reference to"
 263           " function '%s' that does not return a procedure pointer"_err_en_US;
 264   } else if (funcResult->IsProcedurePointer()) {
 265     msg = "Object %s is associated with the result of a reference to"
 266           " function '%s' that is a procedure pointer"_err_en_US;
 267   } else if (!funcResult->attrs.test(FunctionResult::Attr::Pointer)) {
 268     msg = "%s is associated with the result of a reference to function '%s'"
 269           " that is a not a pointer"_err_en_US;
 270   } else if (isContiguous_ &&
 271       !funcResult->attrs.test(FunctionResult::Attr::Contiguous)) {
 272     auto restorer{common::ScopedSet(lhs_, symbol)};
 273     if (Warn(common::UsageWarning::PointerToPossibleNoncontiguous,
 274             "CONTIGUOUS %s is associated with the result of reference to function '%s' that is not known to be contiguous"_warn_en_US,
 275             description_, funcName)) {
 276       return false;
 277     }
 278   } else if (lhsType_) {
 279     const auto *frTypeAndShape{funcResult->GetTypeAndShape()};
 280     CHECK(frTypeAndShape);
 281     if (!lhsType_->IsCompatibleWith(foldingContext_.messages(), *frTypeAndShape,
 282             "pointer", "function result",
 283             /*omitShapeConformanceCheck=*/isBoundsRemapping_ || isAssumedRank_,
 284             evaluate::CheckConformanceFlags::BothDeferredShape)) {
 285       return false; // IsCompatibleWith() emitted message
 286     }
 287   }
 288   if (msg) {
 289     auto restorer{common::ScopedSet(lhs_, symbol)};
 290     Say(*msg, description_, funcName);
 291     return false;
 292   }
 293   return true;
 294 }
 295
 296 template <typename T>
 297 bool PointerAssignmentChecker::Check(const evaluate::Designator<T> &d) {
 298   const Symbol *last{d.GetLastSymbol()};
 299   const Symbol *base{d.GetBaseObject().symbol()};
 300   if (!last || !base) {
 301     // P => "character literal"(1:3)
 302     Say("Pointer target is not a named entity"_err_en_US);
 303     return false;
 304   }
 305   std::optional<std::variant<MessageFixedText, MessageFormattedText>> msg;
 306   if (CharacterizeProcedure()) {
 307     // Shouldn't be here in this function unless lhs is an object pointer.
 308     msg = "In assignment to procedure %s, the target is not a procedure or"
 309           " procedure pointer"_err_en_US;
 310   } else if (!evaluate::GetLastTarget(GetSymbolVector(d))) { // C1025
 311     msg = "In assignment to object %s, the target '%s' is not an object with"
 312           " POINTER or TARGET attributes"_err_en_US;
 313   } else if (auto rhsType{TypeAndShape::Characterize(d, foldingContext_)}) {
 314     if (!lhsType_) {
 315       msg = "%s associated with object '%s' with incompatible type or"
 316             " shape"_err_en_US;
 317     } else if (rhsType->corank() > 0 &&
 318         (isVolatile_ != last->attrs().test(Attr::VOLATILE))) { // C1020
 319       // TODO: what if A is VOLATILE in A%B%C?  need a better test here
 320       if (isVolatile_) {
 321         msg = "Pointer may not be VOLATILE when target is a"
 322               " non-VOLATILE coarray"_err_en_US;
 323       } else {
 324         msg = "Pointer must be VOLATILE when target is a"
 325               " VOLATILE coarray"_err_en_US;
 326       }
 327     } else if (rhsType->type().IsUnlimitedPolymorphic()) {
 328       if (!LhsOkForUnlimitedPoly()) {
 329         msg = "Pointer type must be unlimited polymorphic or non-extensible"
 330               " derived type when target is unlimited polymorphic"_err_en_US;
 331       }
 332     } else {
 333       if (!lhsType_->type().IsTkLenCompatibleWith(rhsType->type())) {
 334         msg = MessageFormattedText{
 335             "Target type %s is not compatible with pointer type %s"_err_en_US,
 336             rhsType->type().AsFortran(), lhsType_->type().AsFortran()};
 337
 338       } else if (!isBoundsRemapping_ &&
 339           !lhsType_->attrs().test(TypeAndShape::Attr::AssumedRank)) {
 340         int lhsRank{lhsType_->Rank()};
 341         int rhsRank{rhsType->Rank()};
 342         if (lhsRank != rhsRank) {
 343           msg = MessageFormattedText{
 344               "Pointer has rank %d but target has rank %d"_err_en_US, lhsRank,
 345               rhsRank};
 346         }
 347       }
 348     }
 349   }
 350   if (msg) {
 351     auto restorer{common::ScopedSet(lhs_, last)};
 352     if (auto *m{std::get_if<MessageFixedText>(&*msg)}) {
 353       std::string buf;
 354       llvm::raw_string_ostream ss{buf};
 355       d.AsFortran(ss);
 356       Say(*m, description_, buf);
 357     } else {
 358       Say(std::get<MessageFormattedText>(*msg));
 359     }
 360     return false;
 361   } else {
 362     context_.NoteDefinedSymbol(*base);
 363     return true;
 364   }
 365 }
 366
 367 // Common handling for procedure pointer right-hand sides
 368 bool PointerAssignmentChecker::Check(parser::CharBlock rhsName, bool isCall,
 369     const Procedure *rhsProcedure,
 370     const evaluate::SpecificIntrinsic *specific) {
 371   std::string whyNot;
 372   std::optional<std::string> warning;
 373   CharacterizeProcedure();
 374   if (std::optional<MessageFixedText> msg{evaluate::CheckProcCompatibility(
 375           isCall, procedure_, rhsProcedure, specific, whyNot, warning,
 376           /*ignoreImplicitVsExplicit=*/isCall)}) {
 377     Say(std::move(*msg), description_, rhsName, whyNot);
 378     return false;
 379   }
 380   if (warning) {
 381     Warn(common::UsageWarning::ProcDummyArgShapes,
 382         "%s and %s may not be completely compatible procedures: %s"_warn_en_US,
 383         description_, rhsName, std::move(*warning));
 384   }
 385   return true;
 386 }
 387
 388 bool PointerAssignmentChecker::Check(const evaluate::ProcedureDesignator &d) {
 389   const Symbol *symbol{d.GetSymbol()};
 390   if (symbol) {
 391     if (const auto *subp{
 392             symbol->GetUltimate().detailsIf<SubprogramDetails>()}) {
 393       if (subp->stmtFunction()) {
 394         evaluate::SayWithDeclaration(foldingContext_.messages(), *symbol,
 395             "Statement function '%s' may not be the target of a pointer assignment"_err_en_US,
 396             symbol->name());
 397         return false;
 398       }
 399     } else if (symbol->has<ProcBindingDetails>()) {
 400       evaluate::AttachDeclaration(
 401           Warn(common::LanguageFeature::BindingAsProcedure,
 402               "Procedure binding '%s' used as target of a pointer assignment"_port_en_US,
 403               symbol->name()),
 404           *symbol);
 405     }
 406   }
 407   if (auto chars{
 408           Procedure::Characterize(d, foldingContext_, /*emitError=*/true)}) {
 409     // Disregard the elemental attribute of RHS intrinsics.
 410     if (symbol && symbol->GetUltimate().attrs().test(Attr::INTRINSIC)) {
 411       chars->attrs.reset(Procedure::Attr::Elemental);
 412     }
 413     return Check(d.GetName(), false, &*chars, d.GetSpecificIntrinsic());
 414   } else {
 415     return Check(d.GetName(), false);
 416   }
 417 }
 418
 419 bool PointerAssignmentChecker::Check(const evaluate::ProcedureRef &ref) {
 420   auto chars{Procedure::Characterize(ref, foldingContext_)};
 421   return Check(ref.proc().GetName(), true, common::GetPtrFromOptional(chars));
 422 }
 423
 424 // The target can be unlimited polymorphic if the pointer is, or if it is
 425 // a non-extensible derived type.
 426 bool PointerAssignmentChecker::LhsOkForUnlimitedPoly() const {
 427   const auto &type{lhsType_->type()};
 428   if (type.category() != TypeCategory::Derived || type.IsAssumedType()) {
 429     return false;
 430   } else if (type.IsUnlimitedPolymorphic()) {
 431     return true;
 432   } else {
 433     return !IsExtensibleType(&type.GetDerivedTypeSpec());
 434   }
 435 }
 436
 437 template <typename... A>
 438 parser::Message *PointerAssignmentChecker::Say(A &&...x) {
 439   auto *msg{foldingContext_.messages().Say(std::forward<A>(x)...)};
 440   if (msg) {
 441     if (lhs_) {
 442       return evaluate::AttachDeclaration(msg, *lhs_);
 443     }
 444     if (!source_.empty()) {
 445       msg->Attach(source_, "Declaration of %s"_en_US, description_);
 446     }
 447   }
 448   return msg;
 449 }
 450
 451 template <typename FeatureOrUsageWarning, typename... A>
 452 parser::Message *PointerAssignmentChecker::Warn(
 453     FeatureOrUsageWarning warning, A &&...x) {
 454   auto *msg{context_.Warn(
 455       warning, foldingContext_.messages().at(), std::forward<A>(x)...)};
 456   if (msg) {
 457     if (lhs_) {
 458       return evaluate::AttachDeclaration(msg, *lhs_);
 459     }
 460     if (!source_.empty()) {
 461       msg->Attach(source_, "Declaration of %s"_en_US, description_);
 462     }
 463   }
 464   return msg;
 465 }
 466
 467 // Verify that any bounds on the LHS of a pointer assignment are valid.
 468 // Return true if it is a bound-remapping so we can perform further checks.
 469 static bool CheckPointerBounds(
 470     evaluate::FoldingContext &context, const evaluate::Assignment &assignment) {
 471   auto &messages{context.messages()};
 472   const SomeExpr &lhs{assignment.lhs};
 473   const SomeExpr &rhs{assignment.rhs};
 474   bool isBoundsRemapping{false};
 475   std::size_t numBounds{common::visit(
 476       common::visitors{
 477           [&](const evaluate::Assignment::BoundsSpec &bounds) {
 478             return bounds.size();
 479           },
 480           [&](const evaluate::Assignment::BoundsRemapping &bounds) {
 481             isBoundsRemapping = true;
 482             evaluate::ExtentExpr lhsSizeExpr{1};
 483             for (const auto &bound : bounds) {
 484               lhsSizeExpr = std::move(lhsSizeExpr) *
 485                   (common::Clone(bound.second) - common::Clone(bound.first) +
 486                       evaluate::ExtentExpr{1});
 487             }
 488             if (std::optional<std::int64_t> lhsSize{evaluate::ToInt64(
 489                     evaluate::Fold(context, std::move(lhsSizeExpr)))}) {
 490               if (auto shape{evaluate::GetShape(context, rhs)}) {
 491                 if (std::optional<std::int64_t> rhsSize{
 492                         evaluate::ToInt64(evaluate::Fold(
 493                             context, evaluate::GetSize(std::move(*shape))))}) {
 494                   if (*lhsSize > *rhsSize) {
 495                     messages.Say(
 496                         "Pointer bounds require %d elements but target has"
 497                         " only %d"_err_en_US,
 498                         *lhsSize, *rhsSize); // 10.2.2.3(9)
 499                   }
 500                 }
 501               }
 502             }
 503             return bounds.size();
 504           },
 505           [](const auto &) -> std::size_t {
 506             DIE("not valid for pointer assignment");
 507           },
 508       },
 509       assignment.u)};
 510   if (numBounds > 0) {
 511     if (lhs.Rank() != static_cast<int>(numBounds)) {
 512       messages.Say("Pointer '%s' has rank %d but the number of bounds specified"
 513                    " is %d"_err_en_US,
 514           lhs.AsFortran(), lhs.Rank(), numBounds); // C1018
 515     }
 516   }
 517   if (isBoundsRemapping && rhs.Rank() != 1 &&
 518       !evaluate::IsSimplyContiguous(rhs, context)) {
 519     messages.Say("Pointer bounds remapping target must have rank 1 or be"
 520                  " simply contiguous"_err_en_US); // 10.2.2.3(9)
 521   }
 522   return isBoundsRemapping;
 523 }
 524
 525 bool CheckPointerAssignment(SemanticsContext &context,
 526     const evaluate::Assignment &assignment, const Scope &scope) {
 527   return CheckPointerAssignment(context, assignment.lhs, assignment.rhs, scope,
 528       CheckPointerBounds(context.foldingContext(), assignment),
 529       /*isAssumedRank=*/false);
 530 }
 531
 532 bool CheckPointerAssignment(SemanticsContext &context, const SomeExpr &lhs,
 533     const SomeExpr &rhs, const Scope &scope, bool isBoundsRemapping,
 534     bool isAssumedRank) {
 535   const Symbol *pointer{GetLastSymbol(lhs)};
 536   if (!pointer) {
 537     return false; // error was reported
 538   }
 539   PointerAssignmentChecker checker{context, scope, *pointer};
 540   checker.set_isBoundsRemapping(isBoundsRemapping);
 541   checker.set_isAssumedRank(isAssumedRank);
 542   bool lhsOk{checker.CheckLeftHandSide(lhs)};
 543   bool rhsOk{checker.Check(rhs)};
 544   return lhsOk && rhsOk; // don't short-circuit
 545 }
 546
 547 bool CheckStructConstructorPointerComponent(SemanticsContext &context,
 548     const Symbol &lhs, const SomeExpr &rhs, const Scope &scope) {
 549   return PointerAssignmentChecker{context, scope, lhs}
 550       .set_pointerComponentLHS(&lhs)
 551       .Check(rhs);
 552 }
 553
 554 bool CheckPointerAssignment(SemanticsContext &context, parser::CharBlock source,
 555     const std::string &description, const DummyDataObject &lhs,
 556     const SomeExpr &rhs, const Scope &scope, bool isAssumedRank) {
 557   return PointerAssignmentChecker{context, scope, source, description}
 558       .set_lhsType(common::Clone(lhs.type))
 559       .set_isContiguous(lhs.attrs.test(DummyDataObject::Attr::Contiguous))
 560       .set_isVolatile(lhs.attrs.test(DummyDataObject::Attr::Volatile))
 561       .set_isAssumedRank(isAssumedRank)
 562       .Check(rhs);
 563 }
 564
 565 bool CheckInitialDataPointerTarget(SemanticsContext &context,
 566     const SomeExpr &pointer, const SomeExpr &init, const Scope &scope) {
 567   return evaluate::IsInitialDataTarget(
 568              init, &context.foldingContext().messages()) &&
 569       CheckPointerAssignment(context, pointer, init, scope,
 570           /*isBoundsRemapping=*/false,
 571           /*isAssumedRank=*/false);
 572 }
 573
 574 } // namespace Fortran::semantics