Issue with a flag that I defined getting set to zero

Gary Oblock
Mon Jan 10 19:53:15 GMT 2022


That's nice to know but I added the option itself months ago.
Also, it's on the lto1 command line, cc1 command line and
shows up in the COLLECT_GCC_OPTIONS so I assume
it universally applied.


From: Richard Biener <>
Sent: Monday, January 10, 2022 12:36 AM
To: Gary Oblock <>
Cc: <>
Subject: Re: Issue with a flag that I defined getting set to zero

[EXTERNAL EMAIL NOTICE: This email originated from an external sender. Please be mindful of safe email handling and proprietary information protection practices.]

On Fri, Jan 7, 2022 at 9:12 AM Gary Oblock via Gcc <> wrote:
> An optimization flag that I recently added is being
> set to zero in push_cfun (which after a couple of
> levels of calls cl_optimization_restore to this.)
> The flag defined like this:
> finterleaving-index-32-bits
> Common Var(flag_interleaving_index_32_bits) Init(0) Optimization
> Structure reorganization optimization, instance interleaving.
> Note, I'm working around this but l'd really like
> to not have to do so therefore I'm wondering if somebody
> could explain what's happening and what I'd need
> to do instead?

Did you rebuild all of GCC after adding the option?  Note that when you
look at the option from LTO and from within an IPA pass then you
have to use opt_for_fn (..) since the "global" option at link time will
be not set (unless you specify it again at link time), it will be only
present on the functions of the compile TU it was set globally.

> Thanks,
> Gary
> CONFIDENTIALITY NOTICE: This e-mail message, including any attachments, is for the sole use of the intended recipient(s) and contains information that is confidential and proprietary to Ampere Computing or its subsidiaries. It is to be used solely for the purpose of furthering the parties' business relationship. Any unauthorized review, copying, or distribution of this email (or any attachments thereto) is strictly prohibited. If you are not the intended recipient, please contact the sender immediately and permanently delete the original and any copies of this email and any attachments thereto.

More information about the Gcc mailing list