On Thu, 22 Feb 2024 16:15:23 GMT, Magnus Ihse Bursie <i...@openjdk.org> wrote:
>> **Summary:** Finally get rid of the mapfiles in Hotspot, and replace it with >> compiler options and `JNIEXPORT` on all platforms. >> >> The bug that this PR solves, >> [JDK-8017234](https://bugs.openjdk.org/browse/JDK-8017234), was created in >> 2013. Even back then the use of mapfiles in Hotspot was dated, so this is >> really good riddance with old rubbish. >> >> This code touches on central but not well understood parts of the Hotspot >> dynamic library, which has contributed to why this bug has stayed unresolved >> for so long. I will need to explain this fix in more detail than usually >> necessary. (Please bare with me if this gets long.) I also anticipate that >> not all solutions that I've picked will be accepted, and we'll have to >> discuss how to proceed. I think it is better to have actual concrete code to >> discuss around, rather than starting by an abstract discussion. To keep this >> description short, I will post the discussion as a comment to the PR. >> >> I have run this PR through tier 1-3 in our CI system. I have also carefully >> checked how the resulting dynamic library differs with this patch (not much; >> see discussion below). For build system changes, this is often the most >> relevant metric. > > Magnus Ihse Bursie has updated the pull request incrementally with one > additional commit since the last revision: > > Use #pragma instead of HIDDEN define Not a review but I did want to mention that I proved to myself that your addition of `.hidden` for the assembly file symbols is the right thing to do. In particular, when we compile the .cpp files with the `-fvisibility=hidden` flag that's exactly what g++ does in the background. Just a thought: Perhaps worth introducing some kind of macro that captures defining a symbol in assembly code (something that does `.globl` + `.hidden` on Linux and `.private_extern` on `__APPLE__`? Also, separate from this change: perhaps worth turning on whitespace checking (no tabs) for .S files? ------------- PR Comment: https://git.openjdk.org/jdk/pull/17955#issuecomment-1960276436
