Bug 15968 - rust-target-config.bbclass: +v5 is not a valid target feature flag
Summary: rust-target-config.bbclass: +v5 is not a valid target feature flag
Status: NEW
Alias: None
Product: OE-Core
Classification: Build System, Metadata & Runtime
Component: devtools / tool chain (show other bugs)
Version: 5.2
Hardware: x86 x86_64
: Medium normal
Target Milestone: 6.2
Assignee: Ross Burton
QA Contact:
URL:
Whiteboard:
Depends on:
Blocks:
 
Reported: 2025-09-09 12:01 UTC by Zixun Li
Modified: 2026-10-27 11:02 UTC (History)
5 users (show)

See Also:
OS type for building Yocto: ---
Type of Regression: ---
Verified:
Documentation change: No (bug/feature does not impact docs)

Attachments
Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.
Description Zixun Li 2025-09-09 12:01:34 UTC 
Following warning is observed while compiling rust program for Microchip SAM9X60 processor (ARM926EJ-S architecture):

'+v5' is not a recognized feature for this target (ignoring feature)

This flag is added by llvm_features_from_tune() from rust-target-config.bbclass.

rustc --print target-features --target arm-poky-linux-gnueabi only have following options for armv5:

v5te                       - Support ARM v5TE, v5TEj, and v5TExp instructions.
armv5t                     - ARMv5t architecture.
armv5te                    - ARMv5te architecture.
armv5tej                   - ARMv5tej architecture.
v5t                        - Support ARM v5T instructions.

It's also not inside llvm's target features llvm/lib/Target/ARM
/ARMFeatures.td
Comment 1 Randy MacLeod 2025-09-11 14:49:02 UTC 
Ross to try to work on identifying the arm version desired.
Comment 2 Richard Purdie 2025-09-11 14:49:47 UTC 
Probably should map to vt5 and error if thumb not available
Comment 3 Ross Burton 2025-09-11 14:50:11 UTC 
What version of yocto was used here? There have been changes to the rust configuration recently.
Comment 4 Zixun Li 2025-09-11 15:13:56 UTC 
(In reply to Ross Burton from comment #3)
> What version of yocto was used here? There have been changes to the rust
> configuration recently.

I'm using v5.2. '+v5' exist from the very beginning since 61e1570.