[wxwidgets] Fix find dependency pcre2

[JackBoosY]

Currently, only the release version of the dependency pcre2 is found during the configuration of wxwidgets, fix this.

Fixes #24851.

[dg0yt]

For x64-linux, the config tool (tools/wxwidgets/wx-config) doesn't report any pcre2 libs. x64-linux is static. I guess there will be a linking issue as soon as pcre2 functions from wxwidgets are actually used. But I can't answer now if this is a regression.

[dg0yt]

But I can't answer now if this is a regression.

It must be a regression. Before this PR, libpcre2-32.a is listed in wx-config.

[JackBoosY]

The value pcre currently left in wx-config is from libsecret-1.pc->glib-2.0.pc in the system:

root@usr:/home/usr/work/24874/vcpkg# find /usr/lib/x86_64-linux-gnu/pkgconfig/ -name *.pc | xargs grep "pcre"
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcre.pc:Name: libpcre
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcre.pc:Libs: -L${libdir} -lpcre
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcreposix.pc:Name: libpcreposix
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcreposix.pc:Description: PCREPosix - Posix compatible interface to libpcre
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcreposix.pc:Libs: -L${libdir} -lpcreposix
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcreposix.pc:Requires.private: libpcre
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcre16.pc:Name: libpcre16
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcre16.pc:Libs: -L${libdir} -lpcre16
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcre32.pc:Name: libpcre32
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcre32.pc:Libs: -L${libdir} -lpcre32
/usr/lib/x86_64-linux-gnu/pkgconfig/libselinux.pc:Requires.private: libsepol libpcre
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcrecpp.pc:Name: libpcrecpp
/usr/lib/x86_64-linux-gnu/pkgconfig/libpcrecpp.pc:Libs: -L${libdir} -lpcre -lpcrecpp
/usr/lib/x86_64-linux-gnu/pkgconfig/glib-2.0.pc:Requires.private: libpcre
/usr/lib/x86_64-linux-gnu/pkgconfig/glib-2.0.pc:Libs.private: -pthread  -lpcre

[JackBoosY]

@dg0yt
The remaining pcre is caused by wxwidgets using the default toolkit gtk3 in linux, it will look for gtk+-3.0.pc in the system, and then use the other installed libraries in systems including pcre.
Then I tried adding gtk as a dependency of wxwidgets, but I get an error:

CMake Error at ports/wxwidgets/portfile.cmake:28 (message):
  Port freetype must not be installed when building wxwidgets:x64-linux.

Seems like this problem is hard to fix at the moment?
Can we ignore this issue for now?

[dg0yt]

If pcre2 is properly referenced in wx-config again, this PR is okay.

Everything else is unrelated:

• I never complained about pcre, the old version of the lib.
• You cannot use gtk (version 4!) for wxwidgets. That's why we need gtk3, [new port] gtk 3.24.34 port #22201.

[JackBoosY]

The default toolkits which we can pick is:

elseif(UNIX)
    set(wxDEFAULT_TOOLKIT gtk3)
    set(wxTOOLKIT_OPTIONS gtk2 gtk3 gtk4 motif qt)
    set(wxPLATFORM UNIX)

We can use qt but it will take more and more build time.

[dg0yt]

The default toolkits which we can pick is:

I know. Qt might be a future feature... but it is pointless: Why use a cross-platform framework on top of another cross-platform framework? I think that developers expect the default, which is gtk3 for Linux.

[ras0219-msft]

set(wxTOOLKIT_OPTIONS gtk2 gtk3 gtk4 motif qt)

I notice that gtk4 is on that list -- progress!

[ras0219-msft]

This LGTM though, thanks!

[dg0yt]

set(wxTOOLKIT_OPTIONS gtk2 gtk3 gtk4 motif qt)

I notice that gtk4 is on that list -- progress!

It is on the list, but it simply won't work soon - not even with wxWidgets 3.4 3.2: https://www.wxwidgets.org/blog/2021/01/wxwidgets-in-2020-and-beyond/

[Playgirlkaybraz11]

#39474 #33955 #39548 #39588 ##39513