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From: "amacleod at redhat dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/101497] [12 Regression] ice in type, at value-range.h:221
Date: Mon, 19 Jul 2021 19:11:10 +0000	[thread overview]
Message-ID: <bug-101497-4-bHTbEWgHZ3@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-101497-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101497

--- Comment #5 from Andrew Macleod <amacleod at redhat dot com> ---
  uc_1.0_1 = uc_1;
  _2 = (int) uc_1.0_1;    
  _3 = 211 - _2;

_3 evaluates as 211 - [-128, 127], or [84, 339]

  _4 = _3 > 0;
  _5 = (int) _4;
  func_12_uli_6 = _5;
  i_4.1_6 = i_4;
  _7 = i_4.1_6 % 0;

We changed it so that anything mod 0 was undefined.  so _7 is UNDEFINED.
  i_4 = _7;
  _11 = _3 > 0;

_3 i s[84, 339] meaning _11 always evaluates TRUE.

  _10 = _11 ? _7 : 0;

The code for COND_EXPR confirms the types match when it folds. In this case,
the result is UNDEFINED.. undefined has no type, so we need to add a check for
that.

  parent reply	other threads:[~2021-07-19 19:11 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-18  7:53 [Bug c/101497] New: " dcb314 at hotmail dot com
2021-07-18  7:58 ` [Bug tree-optimization/101497] [12 Regression] " pinskia at gcc dot gnu.org
2021-07-18  7:58 ` pinskia at gcc dot gnu.org
2021-07-18 16:38 ` dcb314 at hotmail dot com
2021-07-18 16:56 ` dcb314 at hotmail dot com
2021-07-18 17:58 ` dcb314 at hotmail dot com
2021-07-19  6:36 ` rguenth at gcc dot gnu.org
2021-07-19 19:11 ` amacleod at redhat dot com [this message]
2021-07-22 12:53 ` cvs-commit at gcc dot gnu.org
2021-07-22 13:07 ` amacleod at redhat dot com

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