Re: [PATCH] perf: python: Fix build when PYTHON_CONFIG is user supplied

[Ian Rogers]

On Thu, Jul 28, 2022 at 2:40 AM James Clark <james.clark@xxxxxxx> wrote:
>
> The previous change to Python autodetection had a small mistake where
> the auto value was used to determine the Python binary, rather than the
> user supplied value. The Python binary is only used for one part of the
> build process, rather than the final linking, so it was producing
> correct builds in most scenarios, especially when the auto detected
> value matched what the user wanted, or the system only had a valid set
> of Pythons.
>
> Change it so that the Python binary path is derived from either the
> PYTHON_CONFIG value or PYTHON value, depending on what is specified by
> the user. This was the original intention.
>
> This error was spotted in a build failure an odd cross compilation
> environment after commit 4c41cb46a732fe82 ("perf python: Prefer
> python3") was merged.
>
> Fixes: 630af16eee495f58 ("perf tools: Use Python devtools for version autodetection rather than runtime")
> Signed-off-by: James Clark <james.clark@xxxxxxx>

Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks,
Ian

> ---
>  tools/perf/Makefile.config | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
> index d3c254c0f5c6..a69da9f34486 100644
> --- a/tools/perf/Makefile.config
> +++ b/tools/perf/Makefile.config
> @@ -265,7 +265,7 @@ endif
>  # defined. get-executable-or-default fails with an error if the first argument is supplied but
>  # doesn't exist.
>  override PYTHON_CONFIG := $(call get-executable-or-default,PYTHON_CONFIG,$(PYTHON_AUTO))
> -override PYTHON := $(call get-executable-or-default,PYTHON,$(subst -config,,$(PYTHON_AUTO)))
> +override PYTHON := $(call get-executable-or-default,PYTHON,$(subst -config,,$(PYTHON_CONFIG)))
>
>  grep-libs  = $(filter -l%,$(1))
>  strip-libs  = $(filter-out -l%,$(1))
> --
> 2.28.0
>