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From: Harald Anlauf <anlauf@gmx.de>
To: Harald Anlauf <anlauf@gmx.de>
Cc: Jerry DeLisle <jvdelisle@charter.net>,
	fortran <fortran@gcc.gnu.org>,
	gcc-patches <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH] PR libfortran/99218 - [8/9/10/11 Regression] matmul on temporary array accesses invalid memory
Date: Fri, 5 Mar 2021 20:56:17 +0100	[thread overview]
Message-ID: <trinity-6bcff02e-f87b-43c7-895f-5476e4a2c98b-1614974176975@3c-app-gmx-bs16> (raw)
In-Reply-To: <trinity-2f520afb-adff-4bb2-a950-ffeaf4edc291-1614889380854@3c-app-gmx-bs53>

Dear all,

I finally figured out that the array dimensions simply need to be
large enough to get invalid memory accesses that actual lead to a
crash.

I will commit the following testcase along with the fix to libfortran:


! { dg-do run }
! PR libfortran/99218 - matmul on temporary array accesses invalid memory

program p
  implicit none
  integer, parameter :: nState = 300000
  integer, parameter :: nCon = 1
  real,    parameter :: ZERO = 0.0
  real :: G(nCon,nState) = ZERO
  real :: H(nState,nCon) = ZERO
  real :: lambda(nCon)   = ZERO
  real :: f(nState)      = ZERO
  f = matmul (transpose (G), lambda)
  if (f(1) /= ZERO) stop 1
end program


Cheers,
Harald


      reply	other threads:[~2021-03-05 19:56 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-02-23 21:46 Harald Anlauf
2021-03-01 22:19 ` *PING* " Harald Anlauf
2021-03-04  2:16 ` Jerry DeLisle
2021-03-04 20:23   ` Aw: " Harald Anlauf
2021-03-05 19:56     ` Harald Anlauf [this message]

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