[PATCH] build: fix cross compilation to x86_64

[Bruce Richardson]

On Mon, Oct 05, 2026 at 03:14:17PM +0200, Morten Brørup wrote:
> > If x86_64 is specified as target CPU instruction set (e.g. when
> > cross-compiling *to* x86_64), the cpu_instruction_set may be set to
> > x86_64, e.g. if it is derived from a Meson crossfile. However, while
> > Meson uses "x86_64" as name for the x86_64 architecture, compiler
> > options accept only "x86-64".
> > 
> > Introduce a conditional for handling this special case by changing
> > cpu_instruction_set to the march-compatible value.
> > 
> > Signed-off-by: Adrian Schollmeyer <a.schollmeyer at syseleven.de>
> > ---
> >  config/meson.build | 5 +++++
> >  1 file changed, 5 insertions(+)
> > 
> > diff --git a/config/meson.build b/config/meson.build
> > index dcb84ebd13..238d6cae0c 100644
> > --- a/config/meson.build
> > +++ b/config/meson.build
> > @@ -177,6 +177,11 @@ if not is_ms_compiler
> >          machine_args += '-mtune=' + cpu_instruction_set
> >          compiler_arch_support = cc.has_argument('-mcpu=' +
> > cpu_instruction_set)
> >      else
> > +        # Meson uses x86_64, but compilers expect x86-64.
> > +        # See https://mesonbuild.com/Reference-tables.html#cpu-
> > families
> > +        if cpu_instruction_set == 'x86_64'
> > +            cpu_instruction_set = 'x86-64'
> 
> Not sure, but maybe: 'x86-64-v2'?
> 
> Ref:
> https://www.phoronix.com/news/GCC-11-x86-64-Feature-Levels
> 
Yes, probably best to use that. We require SSE4 as a minimum instruction
set for DPDK build.

/Bruce