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From: "burnus at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/90591] Avoid unnecessary data transfer out of OMP construct
Date: Tue, 05 May 2020 14:16:28 +0000	[thread overview]
Message-ID: <bug-90591-4-L7k5yW4mqL@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-90591-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90591

--- Comment #5 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Somewhat related: In terms of OpenMP (to be refined in the spec), the following
applies (in order to work both with shared + nonshared memory):

  int x = 5;
  #pragma omp target map(from:x)
    x = 7;
  printf("%f\n", x);

This code is invalid – which means that the compiler could use this for
optimization and it probably should warn that "x" is used uninitialized.

  parent reply	other threads:[~2020-05-05 14:16 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <bug-90591-4@http.gcc.gnu.org/bugzilla/>
2020-04-20 19:57 ` tschwinge at gcc dot gnu.org
2020-04-21  6:42 ` rguenth at gcc dot gnu.org
2020-04-28 16:53 ` burnus at gcc dot gnu.org
2020-05-05 14:16 ` burnus at gcc dot gnu.org [this message]
2021-03-22 11:37 ` tschwinge at gcc dot gnu.org

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