Record alignment of class in dictionary and use in TStreamerInfo#21669
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pcanal wants to merge 27 commits intoroot-project:masterfrom
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Record alignment of class in dictionary and use in TStreamerInfo#21669pcanal wants to merge 27 commits intoroot-project:masterfrom
pcanal wants to merge 27 commits intoroot-project:masterfrom
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silverweed
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Mar 24, 2026
Test Results 21 files 21 suites 3d 2h 29m 56s ⏱️ Results for commit 556989c. ♻️ This comment has been updated with latest results. |
jblomer
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Mar 27, 2026
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Thanks!
I think it would be nice to have a separate test for AlignOf just for the cling part that exercises the different special cases (forward declaration etc.)
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jblomer
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Apr 11, 2026
jblomer
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Apr 16, 2026
Includes alignment of allocatation of emulated objects in container
Handle alignment for Emulated Collection of pointer and numerical types
Since align is a power of 2 the modulo may be written as (offset & (align - 1)) (assuming offset is non-negative) Co-authored-by: silverweed <giacomo.parolini@cern.ch>
as the fall back when missing alignment information.
Note this is not quite complete, it could also report the alignment when customized at the data member level but it currently does not
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This fixes #21667 and thus addresses CMS issue seen at github.com/cms-sw/cmssw/pull/49969
With the current version storage of collection whose content needs to be aligned with more than 4096 is not supported. Extending it to higher number is trivial but require specific handling for each value so we had to stop at an arbitrary value. The error is seen at dictionary compilation time:
Alignment information has also been added to
TDataType, hence improving (tightening) the alignment of numerical type data member in emulated classes and requiring updates some test reference files.