Re: [PATCH v3] meson: disable PCRE2 dependency by default in macOS

On 7/15/25 8:01 AM, Carlo Arenas wrote:

On Mon, Jul 14, 2025 at 6:55 PM Eli Schwartz [off-list ref] wrote:

quoted

Please double-check my work, that this compiler.has_header() is
sufficient on your reproducer system to detect and disable the
non-working feature.

it is indeed all that was needed, abd makes me wonder
if a future version of dependency() shouldn't have a "has_header"
parameter like the one used in find_libray() to allow for this
validation to happen internally and fallback as needed.

It's... possible, I suppose, but usually not needed unless a distributor
doesn't respond to reports that their OS is broken. Which well, fair
enough, happens. :)

Another possibility is to add a quirk to meson's underlying python code.
If pcre2 is searched, and the platform is darwin, also check the header.
You'll need a small override in mesonbuild/dependencies/*.py, like:


class PCRE2PkgConfigDependency(PkgConfigDependency):
    def __init__(...):
        super().__init__(...)
        if is_darwin:
            self.is_found = check_that_header()

Posted a v4 with your code and modifications to still allow a
fallback to the wrap.

Thanks. :)

-- 
Eli Schwartz