[Bug rtl-optimization/126374] Incorrect codegen with -O2 -fno-tree-sra, struct containing union

carlosgalvezp at gmail dot com via Gcc-bugs <[email protected]> Fri, 24 Jul 2026 13:08:59 +0000

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126374

--- Comment #5 from Carlos Galvez <carlosgalvezp at gmail dot com> ---
Thank you for the inputs!

I tried reverting the added pass, this line:

      NEXT_PASS (pass_fre, false /* may_iterate */);

https://github.com/gcc-mirror/gcc/commit/744fd446c321f78f9a1ce4ef5f83df8dcfa44a9e#diff-71986eb7f13d7073c4843d4cb431491335b9e6d3ed250ce02f02a78e70faad3aR315

And that was enough to continue triggering the issue. Next I arrive to this
other commit also on GCC 10:

https://github.com/gcc-mirror/gcc/commit/ff6686d2e5f797d6c6a36ad14a7084bc1dc350e4

Which sounds like a major related refactor that would likely have fixed the
bug.