Re: [PATCH] xen: Update minimum toolchain requirements

[Nicola Vetrini <nicola.vetrini@bugseng.com>]

On 2025-03-07 18:54, Andrew Cooper wrote:
> GCC 4.1.2 is from 2007, and Binutils 2.16 is a similar vintage.  Clang 
> 3.5 is
> from 2014.  Supporting toolchains this old is a massive development and
> testing burden.
> 
> Set a minimum baseline of GCC 5.1 across the board, along with Binutils 
> 2.25
> which is the same age.  These were chosen *3 years ago* as Linux's 
> minimum
> requirements because even back then, they were ubiquitous in distros.  
> Choose
> Clang/LLVM 11 as a baseline for similar reasons; the Linux commit 
> making this
> change two years ago cites a laudry list of code generation bugs.
> 
> This will allow us to retire a lot of compatiblity logic, and start 
> using new
> features previously unavailable because of no viable compatibility 
> option.
> 
> Merge the ARM 32bit and 64bit sections now they're the same.
> 
> Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
> ---
> CC: Anthony PERARD <anthony.perard@vates.tech>
> CC: Michal Orzel <michal.orzel@amd.com>
> CC: Jan Beulich <jbeulich@suse.com>
> CC: Julien Grall <julien@xen.org>
> CC: Roger Pau Monné <roger.pau@citrix.com>
> CC: Stefano Stabellini <sstabellini@kernel.org>
> CC: Volodymyr Babchuk <Volodymyr_Babchuk@epam.com>
> CC: Bertrand Marquis <bertrand.marquis@arm.com>
> CC: Oleksii Kurochko <oleksii.kurochko@gmail.com>
> CC: Shawn Anastasio <sanastasio@raptorengineering.com>
> 
> PPC doesn't have a minimum set stated yet, but CI tests GCC 10 from 
> Debian 11.
> 
> This will require dropping some containers from CI.  CentOS 7 notably.
> 
> In terms of specific new features, I'm interested in:
> 
>  * __has_include() to remove the asm-generic makefile tangle
>  * asm goto (), to remove .fixup and code generation for error 
> handling.
> 
> and these too, but will require MISRA adjustments:
> 
>  * _Generic() to make properly const-preserving wrappers

Perhaps stating something that is already well-known, but this 
effectively means moving from MISRA C:2012 Amendment 2 as a target to, 
at least, MISRA C:2012 Amendment 3, as that version contains rules in 
series 23 for _Generic.

>  * Updating our -std to gnu11, which drops further compatibility logic
> 
> When the arguments die down, I'll add a hunk to CHANGELOG.md as this is 
> very
> significant.
> ---
>  README | 13 +++++--------
>  1 file changed, 5 insertions(+), 8 deletions(-)
> 
> diff --git a/README b/README
> index 9d9c6fc324c6..be90be3910d4 100644
> --- a/README
> +++ b/README
> @@ -38,16 +38,13 @@ provided by your OS distributor:
>      * GNU Make v3.80 or later
>      * C compiler and linker:
>        - For x86:
> -        - GCC 4.1.2_20070115 or later
> -        - GNU Binutils 2.16.91.0.5 or later
> +        - GCC 5.1 or later
> +        - GNU Binutils 2.25 or later
>          or
> -        - Clang/LLVM 3.5 or later
> -      - For ARM 32-bit:
> -        - GCC 4.9 or later
> -        - GNU Binutils 2.24 or later
> -      - For ARM 64-bit:
> +        - Clang/LLVM 11 or later
> +      - For ARM:
>          - GCC 5.1 or later
> -        - GNU Binutils 2.24 or later
> +        - GNU Binutils 2.25 or later
>        - For RISC-V 64-bit:
>          - GCC 12.2 or later
>          - GNU Binutils 2.39 or later
> 
> base-commit: ac29d63a0fa6a3ed98ecf86f95995811c301308f

-- 
Nicola Vetrini, B.Sc.
Software Engineer
BUGSENG (https://bugseng.com)
LinkedIn: https://www.linkedin.com/in/nicola-vetrini-a42471253