On Thu, 21 Dec 2023 10:01:04 GMT, Thomas Stuefe <stu...@openjdk.org> wrote:
> > > > > What happens if we accidentally attempt to load a "real" static > > > > > library, which is also named *.a? Would dlopen() then crash? What > > > > > would happen? > > > > > > > > > > I don't think the problem is with *.a . They would load as the default > > > > behaviour of the dlopen. It is only when the dlopen fails for *.so , we > > > > give another chance to check for .a file with the same name. > > > > > > > > > No, what I meant, and what must be clarified before going forward with > > > this solution, is the following: > > > > > > * is _every_ `*.a` object on AIX loadable with `dlopen`, and will the > > > result be the same as when loading a `*.so` object > > > * or, if we present arbitrary `*.a` files to dlopen, is there a chance > > > for dlopen to crash or misbehave. > > > > > > Reason is that I was under the impression that *.a libraries are static > > > libraries and cannot be loaded dynamically. This is what you now try to > > > do. > > > If we cannot safely answer this question, I would opt for a more narrow > > > solution by hard-wiring known alternative names. So, do the second *.a > > > attempt only for your `ibm_16_am.a` which you know works. That could also > > > be done in a reasonably maintainable manner. > > > > > > In AIX, both static and dynamic libraries have *.a extension. And AIX also > > supports *.so files.Bascially shared objects in AIX have both *.a and *.so > > extension. Hence we need to implement this logic. If we try loading a > > static archive specifically ,how the dlopen would behave , that is > > something probably @JoKern65 can answer ? > > Rather, this is a question you have to ask your collegues at IBM that develop > the AIX libc. > > Since AIX libc is not open source, we cannot look for ourselves, nor can > Joachim (her works at SAP). > > > > > > Does this really have to be handled in the OpenJDK? What does J9 on > > > > > AIX do? Could this be done in a simpler way outside OpenJDK, e.g. by > > > > > providing an *.so variant of the library in question? Where does this > > > > > library come from? > > > > > > > > > > I am not sure how J9 handles this. I would have to consult . > > > > > > > > > J9 is Open Source, can't you just look? :) > > > > > > I did try comparing the file structures, and i do not see a similar file > > structure over there. I am unable to find the jvmTiAgent code and also > > os_aix file. So i am not sure which functions over there are doing the same > > functionality. You have any suggestion on how i can check and correlate ? > > Someone must implement LoadLibrary. Try looking for places where dlopen() is > called. > > > > > However as per current observation, this issue does not show up on > > > > Semuru. This issue is only happening on Adoptium. The team that release > > > > these file has always released *.a files which work fine for Semuru. > > > > > > > > > I don't know what Semuru is. What is the context, is that a different VM? > > > Also OpenJDK? J9 derived? > > > > > > Semuru is J9 derived. Ok , i was not able to find the right file yet. I will collaborate on this further once i am back from vacation, in January. ------------- PR Comment: https://git.openjdk.org/jdk/pull/16604#issuecomment-1867498645
