[Bug tree-optimization/126650] [13/14/15 Regression] Wrong code at -O2/3/s on x86_64-pc-linux-gnu

"cvs-commit at gcc dot gnu.org via Gcc-bugs" <[email protected]> Wed, 19 Aug 2026 09:45:08 +0000

Newsgroups	gmane.comp.gcc.bugs
Message-ID	<[email protected]/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126650

--- Comment #7 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-15 branch has been updated by Richard Biener
<[email protected]>:

https://gcc.gnu.org/g:ba07588cc97d103842e1eac10065689321d97b56

commit r15-11491-gba07588cc97d103842e1eac10065689321d97b56
Author: Richard Biener <[email protected]>
Date:   Wed Aug 5 10:31:47 2026 +0200

    tree-optimization/126650 - get_inner_reference_aff and bitfields

    get_inner_reference_aff tries to compensate for bit precision
    offsets and sizes by rounding down and up, but fails to do this
    correctly.  The following makes it more obviously correct by
    rounding positions and computing the rounded size based on those.

            PR tree-optimization/126650
            * tree-affine.cc (get_inner_reference_aff): Fixup rounding
            of size.

            * gcc.dg/torture/pr126650.c: New testcase.

    (cherry picked from commit 9baaca2adeca178edf8c0816ef328dba1cf270bc)