[Lldb-commits] [PATCH] D86311: Fix how ValueObjectVariable handles DW_AT_const_value when the DWARFExpression holds the data that represents a constant value

[Shafik Yaghmour via Phabricator via lldb-commits]

shafik created this revision.
shafik added reviewers: aprantl, friss, labath, jingham, vsk.
shafik requested review of this revision.
Herald added a reviewer: jdoerfert.
Herald added a subscriber: sstefan1.

In some cases when we have a `DW_AT_const_value` and the data can be found in the `DWARFExpression` then `ValueObjectVariable` does not handle it properly and we end up with an `extracting data from value failed` error:

  (lldb) target var constant
  (U) constant = {
    raw = <extracting data from value failed>
  
     = (a = <extracting data from value failed>, b = <extracting data from value failed>, c = <extracting data from value failed>, d = <extracting data from value failed>, e = <extracting data from value failed>, f = <extracting data from value failed>)
  }

This should fix that case.

The test is a very stripped down assembly file since reproducing this relies on the results of compiling with `-O1` which may not be stable over time.


https://reviews.llvm.org/D86311

Files:
  lldb/source/Core/ValueObjectVariable.cpp
  lldb/test/Shell/SymbolFile/DWARF/DW_AT_const_value.s

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