Plan to remove dead C++ UNO bridge implementations (bridges/source/cpp_uno/*)

[Stephan Bergmann]

On 10/01/2023 17:31, Stephan Bergmann wrote:
> There are currently 27 different, per-platform C++ UNO bridge 
> implementations at bridges/source/cpp_uno/, some of which are presumably 
> dead by now.  And my recent 
> <https://git.libreoffice.org/core/+/ef533553559fe09b4afab651fc692885d1acf4ed%5E!/> "Rudimentary support for dynamic_cast on UNO proxy objects" (which had to touch each of them individually) was the latest example how even presumably dead ones have ongoing maintenance cost.  Therefore, I would like to remove (on master, towards LO 7.6) the ones that can clearly be identified as being dead.
> 
> Below, I sorted those 27 implementations into 5 categories:  Ideally, 
> each active implementation would be built regularly by Jenkins; those 9 
> that are go into category 1.  Next, there are 2 additional 
> implementations that I know are built for Fedora releases; they go into 
> category 2.  Next, there are 2 additional implementations that I presume 
> are built for Debian releases (Rene, correct me if I'm wrong); they go 
> into category 3.  And then there are 3 implementations that are 
> presumably in active use elsewhere (Tor, wjh-la, Sakura286, correct me 
> if I'm wrong); which go into category 4.  That leaves 11 implementations 
> that are presumably dead, in category 5.
> 
> So if you know about any active use of any of those 11 implementations 
> in category 5 below, please report back here.  Otherwise, the plan (to 
> be discussed in the ESC) is to eventually remove them in due course.
[...]
> (5) Presumably dead:
> 
> * gcc3_aix_powerpc
> 
> * gcc3_linux_alpha
> 
> * gcc3_linux_hppa
> 
> * gcc3_linux_ia64
> 
> * gcc3_linux_m68k
> 
> * gcc3_linux_powerpc
> 
> * gcc3_linux_s390
> 
> * gcc3_linux_sparc
> 
> * gcc3_linux_sparc64
> 
> * gcc3_solaris_intel
> 
> * gcc3_solaris_sparc

With the various responses to this mailing list thread, that list of 
presumably dead bridge implementations is down to four now: 
gcc3_aix_powerpc, gcc3_linux_s390, gcc3_solaris_intel, and 
gcc3_solaris_sparc.

I have prepared three sets of Gerrit changes (see below) to remove those 
four bridge implementations and, in some cases, complete platform 
support, and plan to submit those on LO master towards LO 7.6 after a 
final round of discussions in Thursday's ESC meeting.

* <https://gerrit.libreoffice.org/c/core/+/146057> and 
<https://gerrit.libreoffice.org/c/help/+/146063> "Remove support for AIX":

> As discussed in the mailing list thread starting at
> <https://lists.freedesktop.org/archives/libreoffice/2023-January/089808.html>
> "Plan to remove dead C++ UNO bridge implementations (bridges/source/cpp_uno/*)",
> the bridge implementation at bridges/source/cpp_uno/gcc3_aix_powerpc is
> apparently dead and should thus be removed.  However, that was the only bridge
> implementation for AIX, which implies that support for the AIX platform as a
> whole is dead and should thus be removed.

* <https://gerrit.libreoffice.org/c/core/+/146058> "Remove support for 
32-bit S390":

> As discussed in the mailing list thread starting at
> <https://lists.freedesktop.org/archives/libreoffice/2023-January/089808.html>
> "Plan to remove dead C++ UNO bridge implementations (bridges/source/cpp_uno/*)",
> the bridge implementation at bridges/source/cpp_uno/gcc3_linux_s390 is
> apparently dead and should thus be removed.  However, that was the only bridge
> implementation for 32-bit S390, which implies that support for the 32-bit S390
> architecture as a whole is dead and should thus be removed.

* <https://gerrit.libreoffice.org/c/core/+/146059> "Remove Solaris 
32-bit SPARC and x86 C++ UNO bridge implementations":

> As discussed in the mailing list thread starting at
> <https://lists.freedesktop.org/archives/libreoffice/2023-January/089808.html>
> "Plan to remove dead C++ UNO bridge implementations (bridges/source/cpp_uno/*)",
> the bridge implementations at bridges/source/cpp_uno/gcc3_solaris_intel and
> bridges/source/cpp_uno/gcc3_solaris_sparc are apparently dead and should thus be
> removed.  Those were the only bridge implementations for Solaris, but the
> referenced thread mentions that there are recent builds for OpenIndiana x86-64
> (however they are done; presumably using
> bridges/source/cpp_uno/gcc3_linux_x86-64), so keep general support for Solaris
> intact for now.