sja@sirius.hut.fi (Sakari Jalovaara) (03/22/91)
Has anyone made shared Motif 1.1.1 libraries on an IBM RS/6000?
I don't seem to be able to make them work. If Motif programs are
linked statically they work but if any or all of Mrm, Xm or Xt are
shared libraries some programs give errors like
Warning:
Name: work_area
Class: XmForm
Null font list (no vendor shell default)
some die with "Error: Unresolved inheritance operation" and keyboard
input kills all programs. Does this sound familiar to anyone?
(IBM RISC System/6000 540, AIX 3.1 patch 3003, Motif 1.1.1, MIT X11R4
patch 18 with rs-6000.fix1 and rs-6000.fix2 from export.lcs.mit.edu
and a partridge in a pear tree.)
++sjadan@IBM.COM (Walt Daniels) (03/23/91)
>Has anyone made shared Motif 1.1.1 libraries on an IBM RS/6000? >Jalovaara It is a known problem and being worked on. The problem appears to be that there is a Vendor.c in both Xt and Xm and the wrong one is used because of the shared library implementation. I am not enough of an expert on Xt to be sure but roughly what has to be done is similar to what SUN has done to solve their shared library problems. You have to hook Vendor.c in Xt and create an additional pointer to the pointer to the vendor class stuff. You also have to hook XtToolkitInitialize to put the right address in that pointer. You then need to build a shared Xt that has sharedlib.c marked as unshared. If this hint is enough to get it working let me know. If it is flawed I would also be interested. I will in fact try to generate and test such a solution sometime after next week. If I solve the problem I will give the solution to the product people. Meanwhile the "real" product people are also working on the problem. You should report the problem though your normal problem reporting process, 1-800-237-5511 (you need to know your customer number). That way you should get notified when a fix is available. Walt Daniels IBM Research (not part of the product division)
sja@sirius.hut.fi (Sakari Jalovaara) (03/24/91)
I wrote: > Has anyone made shared Motif 1.1.1 libraries on an IBM RS/6000? > > I don't seem to be able to make them work. If Motif programs are > linked statically they work but if any or all of Mrm, Xm or Xt are > shared libraries some programs give errors [...] Two people, Kaleb Keithley at JPL and Kee Hinckley at Alfalfa Software Inc, knew what was happening: Xm redefines VendorShell and the AIX linker put _both_ Xm's and Xt's VendorShell into programs. When an AIX shared library is created as many references inside the library are resolved as possible. If the symbol vendorShellClassRec is defined in libXt and referenced, say, from a function XtFoo() also in libXt, the "ld" run that creates the shared library resolves the reference: XtFoo() -> vendorShellClassRec Then I create the Motif library that has its own vendorShellClassRec and an XmBar() function that uses it; libXm will also contain a resolved reference to vendorShellClassRec: XmBar() -> vendorShellClassRec Finally, I link a program that uses both XtFoo() and XmBar() and the program will end up with _two_ independent "vendorShellClassRec"s: XtFoo() -> vendorShellClassRec [Xt version] XmBar() -> vendorShellClassRec [Xm version] Instand schizo zaphod mode. In reality, vendorShellClassRec is not referenced from functions but from other widget class records. I can't just pull Vendor.o out from the shared Xt (Vendor.o appears to define the only external symbols redefined by libXm) because AIX shared libraries apparently can't contain unresolved external references. If I take out Vendor.o I have to take out every other file that uses symbols defined there - and then files that need those files, etc. I tried it and ended up with three or four object files in libXt and the res non-sharable. I kludged around this by putting all of libXt (minus Vendor.o) into the shared libXm. It isn't a pretty solution but it works - and beats having a statically linked two-megabyte "periodic" demo... ++sja