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From: "ibuclaw at gdcproject dot org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug d/101691] New: d: Use of LOOP_EXPR prevents removing no-op loops.
Date: Fri, 30 Jul 2021 10:35:27 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101691

            Bug ID: 101691
           Summary: d: Use of LOOP_EXPR prevents removing no-op loops.
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: d
          Assignee: ibuclaw at gdcproject dot org
          Reporter: ibuclaw at gdcproject dot org
  Target Milestone: ---

As observed on compiler explorer.

https://d.godbolt.org/z/eM8Pv91eT

The C, C++ (and Fortran?) front-ends lower loops as labels and gotos, which
*is* optimized away.

https://godbolt.org/z/8Yz9oqx63

---
void fun(int a, int b, int step)=20
{
    for (int i =3D a; i < b; i +=3D step) {
    }
}=