Re: Duplicate libraries in fox-config output

It was a POSIX requirement.

Best to put the things in: --start-group   --end-group   because by 
default the linker is still single pass.

On 7/26/2024 7:18 AM, [email protected] wrote:
> On 2024-07-26 07:04, Roland Hughes via Foxgui-users wrote:
>> Unknown if it ever impacted FOX, but many years ago, one had to. Gray
>> cells are a bit fuzzy on it, had to do with video card flavored
>> libraries and a few third party libraries that would not find one
>> library if it was linked ahead of it.
>>
>> In what could only be an MBA lead "efficiency" move most linkers of
>> the day were single pass. While you should never ever under any
>> circumstances trust anything on StackOverflow, the answer from this 11
>> year old question with a green check mark and 123 up votes does a
>> pretty good job of explaining it.
>>
>> https://stackoverflow.com/questions/11893996/why-does-the-order-of-l-option-in-gcc-matter 
>>
>>
>> Thanks to brain dead AI additions to search engines you can no longer
>> search for "how many passes does GNU linker make" without getting
>> inundated with links to command line passing.
>>
>> The comments below that answer tick some memories too. You have to
>> remember the x86 has always been and will probably always be the home
>> hobby platform. When Intel and Microsoft desperately wanted to get a
>> to hold in Fortune 500 data centers they bribed marketing agencies
>> like Gartner Group (masquerading as "industry analysts") telling
>> companies that systems and libraries needed to conform to "Open
>> Standards." Prior to that we had things that actually worked. Your
>> OS/400 programs just worked on OS/400. MVS on MVS. VMS on VMS, etc. We
>> had screen and other libraries all made by the hardware vendor for the
>> hardware and OS we were running on. No, they weren't portable, but
>> they "just worked." We used operating systems that were created to be
>> robust multi-user platforms that could bill for every byte and clock
>> cycle consumed by everyone. It wasn't until MAI, Wang, and a few
>> others started going under that portable became something companies
>> worried about. We had proprietary security until the vendor went
>> under. We also had linkers that operated in one of the following
>> manners:
>>
>> 1) Made N-passes through the libraries trying to resolve external
>> linkage. You had a command line switch to limit the maximum number of
>> passes. Something says the default for most was up to 4 passes.
>>
>> 2) Loaded _every_ external linkage item from every library on the
>> command line into one big lookup table before linking object files.
>> (Our libraries had header areas where all this info was so they were
>> only reading a few disk blocks from each, not dynamically parsing
>> something.)
>>
>> 3) Both 1 & 2. Towards the end this was what they all did because
>> every time you linked another function from another library it could
>> add new external dependencies.
>>
>> After the bust-up of AT&T, UNIX, originally created on a DEC PDP,
>> which was never created to be a true multi-user OS, just to run phone
>> switches and allow maintenance to log in to tweak/update things, got
>> popped out into the world of "free software." There might have been as
>> many as 60 commercial Unix versions that popped up in the weeks/months
>> following. Most of them sucked. None of them were worthy of running a
>> business on, though some companies tried. These vendors desperately
>> wanted to get into the corporate data center as well. That's where the
>> real money was.
>>
>> You may remember a name called SUN Microsystems. When you could cobble
>> together a generic PC with 40MEG hard drive and two floppies for
>> around $800, SUN was selling $20,000 "engineering workstations" to
>> corporations that cost about the same to build. They had cash coming
>> out their back side and got behind this "standard." There was no way
>> they were ever going to get their
>> not-really-multi-user-just-multiple-people-could-log-in system into
>> the data center unless they could somehow make that sexy to the ones
>> with the checkbooks.
>>
>> Enter POSIX.
>>
>> A standard that busted every proprietary OS trying to conform to it
>> because the ones holding the checkbooks demanded compliance with it.
>> With POSIX we got insecurities, data breaches, and a mandate for a
>> single pass linker because that is all the
>> not-really-multi-user-just-multiple-people-could-log-in systems could
>> manage.
>>
>> Your latest macOS is not POSIX compliant. You should point it out to
>> them since Apple was one of the companies behind POSIX back in the
>> day. SUN, creators of Java with seemingly limitless financial
>> resources, went bankrupt.
>>
>> As part of this POSIX world Microsoft wanted to make a standard for
>> user interaction. They wanted it to be like their feeble DOS and GUI
>> DOS (Windows) was capable of. After the initial POSIX debacle IBM
>> flooded the standards committee with employees and customers. That is
>> why CUA works exactly like a CICS application on a green screen. We
>> tab between fields, have a special ENTER key different from the RETURN
>> key, etc.
>>
>> Why do those of us who worked on real computers have such disdain for
>> the x86 platforms despite all of the embedded, Linux, and desktop
>> stuff we have written?
>>
>> On the PDP 11/70 we ran 255 interactive/batch users in 64K-words. The
>> PC with DOS and 640K bytes could barely run one.
>>
>> The current IBM z/OS box, a little shorter and about the same width as
>> 2 4-drawer file cabinets can run more users that 2 complete floors of
>> machines at any cloud data center in the world. I don't think they
>> worried about POSIX compliance.
>>
>> Sorry, the "why" behind your answer is tangled up in an ugly corrupt
>> history of the PC world. It appears macOS has now learned the ugly
>> truth. POSIX was meant to cripple, not enhance.
>>
>> When you are written for the least common denominator and all must
>> comply, nobody can soar.
>>
>> Even GNU has figured this out and quietly hidden their nasty undies
>> --  GNU is no longer POSIX compliant. Read up on:
>>
>> --whole-archive      (links everything just like we did with DOS)
>>
>> --start-group   --end-group    (make N-passes through these libraries
>> trying to resolve linkage)
>>
>>
>>
>> On 7/26/2024 2:02 AM, Michael Behrisch via Foxgui-users wrote:
>>> Hi,
>>> I have a question about the output of "fox-config --libs".
>>> On my system it currently gives: "-L/usr/lib64 -lFOX-1.6 -lX11 
>>> -lXext -lfreetype -lfontconfig -lXft -lXcursor -lXrender -lXrandr 
>>> -lXfixes -lXi -lGL -lGLU -ldl -lpthread -lrt -ljpeg -lpng -ltiff -lz 
>>> -lbz2 -lGLU -lGL"
>>> which duplicates the GL and GLU libraries.
>>>
>>> The problem is that recent macOS builds complain if you link the 
>>> same library twice.
>>>
>>> I had a look at the source code in configure.ac and fox-config.in 
>>> and this seems to be intentional because indeed the GL libraries 
>>> (LIBGL) are being added to the LIBS variable and then both are 
>>> output in the end.
>>> I removed the first addition of the GL libs and it is still working 
>>> fine here but before submitting a patch I wanted to ask whether 
>>> there is a known reason for this duplication because sometimes the 
>>> linker is tricky.
>>>
>>> Thank you and best regards,
>>> Michael
>
>
> W.r.t. search engines, Google, Bing are no longer search engines. You
> won't find anything with these.
>
> I recommend xmol, presearch, and yandex.
>
> ===
>
> Yes, it is indeed sometimes necessary to repeat same library, because 
> sometimes stuff was not possible to be arranged so all references were 
> forward.
>
> However, it is possible current linkers are no longer having this 
> problem;
> maybe it was a a.out limitation, or maybe it only applies to .a linkage
> and .so links [which are resolved at runtime] do not have this problem...
>
>
>   -- JVZ
>
>
>
>  -- JVZ

-- 
Roland Hughes, President
Logikal Solutions
(630)-205-1593  (cell)
https://theminimumyouneedtoknow.com
https://infiniteexposure.net
https://johnsmith-book.com



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