Fix PDB Symbol Resolution for Unmerged Windows Traces#2407
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brianrob merged 2 commits intomicrosoft:mainfrom Apr 9, 2026
Merged
Fix PDB Symbol Resolution for Unmerged Windows Traces#2407brianrob merged 2 commits intomicrosoft:mainfrom
brianrob merged 2 commits intomicrosoft:mainfrom
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The ELF symbol work introduced a switch on BinaryFormat in LookupSymbolsForModule that only handled PE and ELF cases. For unmerged Windows traces, symbolInfo is null (no RSDS events in the ETL), so BinaryFormat returns Unspecified, causing symbol resolution to be skipped entirely. Add a case for ModuleBinaryFormat.Unspecified that falls back to PDB lookup on Windows. OpenPdbForModuleFile handles missing PDB signatures gracefully by checking the local file on disk. Also rename ModuleBinaryFormat.Unknown to Unspecified to better reflect that the format was not specified in the trace data. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
leculver
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Non blocking question, otherwise looks good.
| // didn't contain RSDS events with PDB identity info. | ||
| // Fall back to PDB lookup on Windows, which handles missing signatures | ||
| // gracefully and returns null if the file isn't a PE binary. | ||
| if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) |
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IsOSPlatform is the right function here? I mean yes we will process ETL files on windows, but there's no "target we are analyzing" concept?
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Yes. I was being intentional about making sure this happens specifically on a Windows machine because we use msdia underneath.
This was referenced Apr 10, 2026
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The ELF symbol work introduced a switch on
BinaryFormatinLookupSymbolsForModulethat only handledPEandELFcases. For unmerged Windows traces,symbolInfois null because the ETL doesn't contain RSDS events with PDB identity info. This causedBinaryFormatto returnUnspecified(formerlyUnknown), hitting the default case which skipped symbol resolution entirely.Symptoms:
Fix:
case ModuleBinaryFormat.Unspecifiedthat falls back to PDB lookup when running on Windows.OpenPdbForModuleFilealready handles missing PDB signatures gracefully by checking the local file on disk.ModuleBinaryFormat.UnknowntoUnspecifiedto better reflect that the format was not specified in the trace data rather than being truly unknown.