[flang-commits] [flang] [flang] Fix crash in HLFIR generation (PR #118399)

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llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-flang-fir-hlfir

Author: Peter Klausler (klausler)

<details>
<summary>Changes</summary>

Structure constructors with multiple components would crash when components were from parent types.  The search for the right parent component must be done anew for each component.

Fixes https://github.com/llvm/llvm-project/issues/118270.

---
Full diff: https://github.com/llvm/llvm-project/pull/118399.diff


1 Files Affected:

- (modified) flang/lib/Lower/ConvertExprToHLFIR.cpp (+5-6) 


``````````diff
diff --git a/flang/lib/Lower/ConvertExprToHLFIR.cpp b/flang/lib/Lower/ConvertExprToHLFIR.cpp
index e93fbc562f9b13..4ab319b016caf7 100644
--- a/flang/lib/Lower/ConvertExprToHLFIR.cpp
+++ b/flang/lib/Lower/ConvertExprToHLFIR.cpp
@@ -1696,18 +1696,17 @@ class HlfirBuilder {
     // required chains of hlfir.designate to address the parent components so
     // that the StructureConstructor can later be lowered by addressing these
     // parent components if needed. Note: the front-end orders the components in
-    // structure constructors. The code below relies on the component to appear
-    // in order.
+    // structure constructors.
     using ValueAndParent = std::tuple<const Fortran::lower::SomeExpr &,
                                       const Fortran::semantics::Symbol &,
                                       hlfir::EntityWithAttributes>;
     llvm::SmallVector<ValueAndParent> valuesAndParents;
-    Fortran::lower::ComponentReverseIterator compIterator(
-        ctor.result().derivedTypeSpec());
-    hlfir::EntityWithAttributes currentParent = varOp;
     for (const auto &value : llvm::reverse(ctor.values())) {
       const Fortran::semantics::Symbol &compSym = *value.first;
-      while (!compIterator.lookup(compSym.name())) {
+      hlfir::EntityWithAttributes currentParent = varOp;
+      for (Fortran::lower::ComponentReverseIterator compIterator(
+               ctor.result().derivedTypeSpec());
+           !compIterator.lookup(compSym.name());) {
         const auto &parentType = compIterator.advanceToParentType();
         llvm::StringRef parentName = toStringRef(parentType.name());
         auto baseRecTy = mlir::cast<fir::RecordType>(

``````````

</details>


https://github.com/llvm/llvm-project/pull/118399