[PATCH] D102713: [PDB] Improve error handling when writes fail

[Alexandre Ganea via Phabricator via llvm-commits]

aganea added a comment.

We had similar OOM issues on the bots, as mentionned in the two bug reports. Regarding https://bugs.chromium.org/p/chromium/issues/detail?id=1179085, if you're using `/DEBUG:GHASH` the following patch might fix it? (but still generates > 4 GB .PDBs, which is probably a merging bug)

  diff --git a/lld/COFF/DebugTypes.cpp b/lld/COFF/DebugTypes.cpp
  index fedcb054540f..8bd8723f4bf2 100644
  --- a/lld/COFF/DebugTypes.cpp
  +++ b/lld/COFF/DebugTypes.cpp
  @@ -1064,7 +1064,8 @@ void TypeMerger::mergeTypesWithGHash() {
   
     // Cap the table size so that we can use 32-bit cell indices. Type indices are
     // also 32-bit, so this is an inherent PDB file format limit anyway.
  -  tableSize = std::min(size_t(INT32_MAX), tableSize);
  +  tableSize =
  +      std::min(size_t(INT32_MAX) - TypeIndex::FirstNonSimpleIndex, tableSize);
     ghashState.table.init(static_cast<uint32_t>(tableSize));
   
     // Insert ghashes in parallel. During concurrent insertion, we cannot observe

The issue was that `source->indexMapStorage[i] = TypeIndex::fromArrayIndex(cellIdx);` would store invalid offsets since the high bit (`DecoratedItemIdMask`) is dismissed when doing `TypeIndex::toArrayIndex()`.


Repository:
  rG LLVM Github Monorepo

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https://reviews.llvm.org/D102713