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[charm] vector< bool >

From: Jozsef Bakosi <jbakosi AT lanl.gov>
To: charm AT lists.cs.illinois.edu
Cc: "Pandare, Aditya Kiran" <apandare AT lanl.gov>
Subject: [charm] vector< bool >
Date: Thu, 12 Dec 2019 08:51:08 -0700
Authentication-results: illinois.edu; spf=pass smtp.mailfrom=jbakosi AT lanl.gov; dkim=pass header.d=lanl.gov header.s=lanl; dmarc=pass header.from=lanl.gov

Hi folks,

We have recently run into a very nasty problem that was pretty hard to
diagnose: serializing a std::vector< bool > corrupts its contents and
will yield dissimilar data on different PEs. We fixed the problem by
using std::vector< int > instead, which serializes correctly.

The problem with std::vector< bool > is somewhat well-known, see e.g.,
https://stackoverflow.com/questions/17794569/why-is-vectorbool-not-a-stl-container/17794965#17794965,
and this is probably the cause of the erroneous behavior with the
serialization machinery.

It would be very user-friendly if Charm++ handled this special case
correctly.

Thanks,
Jozsef

[charm] vector< bool >, Jozsef Bakosi, 12/12/2019
- <Possible follow-up(s)>
- Re: [charm] vector< bool >, Sam White, 12/12/2019
  - Re: [charm] vector< bool >, Jozsef Bakosi, 12/12/2019