[llvm] [NFC][DebugInfo] Wrap DILineInfo return type with std::optional to handle missing debug info. (PR #129792)

[David Blaikie via llvm-commits]

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@@ -131,7 +137,8 @@ PDBContext::getInliningInfoForAddress(object::SectionedAddress Address,
     InlineInfo.addFrame(LineInfo);
   }
 
-  InlineInfo.addFrame(CurrentLine);
+  if (CurrentLine)
+    InlineInfo.addFrame(*CurrentLine);
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dwblaikie wrote:

I'd expect this (& similar things above) to change behavior, does it not?
Do all callers handle a frame that's default constructed the same as the absence of a frame?

https://github.com/llvm/llvm-project/pull/129792