[clang] [DebugInfo] Add flag to only emit referenced member functions (PR #87018)

[Stephen Tozer via cfe-commits]

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@@ -2755,7 +2755,7 @@ CGDebugInfo::CreateTypeDefinition(const RecordType *Ty) {
 
   // Collect data fields (including static variables and any initializers).
   CollectRecordFields(RD, DefUnit, EltTys, FwdDecl);
-  if (CXXDecl)
+  if (CXXDecl && !CGM.getCodeGenOpts().DebugOmitUnreferencedMembers)
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SLTozer wrote:

>From the old review, there was a question about whether this should be disabled by `-fstandalone-debug` - it seemed like there was a reasonable case for (being able to call member functions from a different TU without debug info), and a reasonable case against (inconsistency with non-member functions), and it's not totally clear whether that was resolved.

https://github.com/llvm/llvm-project/pull/87018