[clang] [DebugInfo] Ignore delegating constructors in constructor homing. (PR #218807)

[David Blaikie via cfe-commits]

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@@ -27,6 +27,39 @@ struct E {
   constexpr E(){};
 } TestE;
 
+// Defined delegating constructor where delegated constructor is not defined
+// should not emit full debug info.
+// CHECK-DAG: !DICompositeType(tag: DW_TAG_structure_type, name: "Delegating"{{.*}}flags: DIFlagFwdDecl
+struct Delegating {
+  Delegating() : Delegating(42) {}
+  Delegating(int);
+} TestDelegating;
+
+// Defined delegating constructor where delegated constructor is defined should
+// emit full debug info.
+// CHECK-DAG: !DICompositeType(tag: DW_TAG_structure_type, name: "DelegatingToDefined"{{.*}}DIFlagTypePassByValue
+struct DelegatingToDefined {
+  DelegatingToDefined() : DelegatingToDefined(42) {}
+  DelegatingToDefined(int) {}
+} TestDelegatingToDefined;
+
+// Defined out-of-line delegating constructor where delegated constructor is
+// defined should emit full debug info.
+// CHECK-DAG: !DICompositeType(tag: DW_TAG_structure_type, name: "DelegatingOutOfLine"{{.*}}DIFlagTypePassByValue
+struct DelegatingOutOfLine {
+  DelegatingOutOfLine();
+  DelegatingOutOfLine(int) {}
+};
+DelegatingOutOfLine d;
+DelegatingOutOfLine::DelegatingOutOfLine() : DelegatingOutOfLine(42) {}
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dwblaikie wrote:

Perhaps add a test case for both sides of that scenario (delegating ctor declared-but-not-defined, inline ctor that is delegated to - one version with the delegating ctor defined (type should be defined), one version without it defined (type should not be emitted))

https://github.com/llvm/llvm-project/pull/218807