RFR: 8317510: Change Windows debug symbol files naming to avoid losing info when an executable and a library share the same name [v3]

[Julian Waters]

On Mon, 9 Oct 2023 10:21:58 GMT, Frederic Thevenet <fthevenet at openjdk.org> wrote:

>> When building OpenJDK on Windows using "--with-native-debug-info=external", the resulting debug symbols are saved in files located in the same folder as the corresponding executable or library and named by swapping the extension ".exe" or ".dll" for a ".pdb" one (or "diz" if option "--with-native-debug-info=zipped" is used), which means that in the event of an exe and a dll file sharing the same target folder and file name (e.g. `bin\java.exe` and `bin\java.dll`), we have to choose whether symbols in `bin\java.pdb` will refer to the exe or the dll; we can't have both.
>> 
>> This PR addresses this issue by adopting a different naming strategy for the resulting symbol files where we keep the full name of every file - including its `dll` or `exe` extension) and then add the appropriate `.pdb`, `.map` or `.diz` extension .
>> 
>> For instance,  `jvm.dll` symbols are no longer called `jvm.pdb` but instead `jvm.dll.pdb`. Similarly, it is now `jvm.dll.diz` when using zipped symbols, and "jvm.dll.stripped.pdb" for stripped symbols (i.e. when "--with-external-symbols-in-bundles=public" is used).
>> 
>> The PR also removes the existing filtering for java.pdb, jimage.pdb and jpackage.pdb used to guaranty the dll symbols were bundled over the ones from the exe, since we no longer need that.
>
> Frederic Thevenet has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Added a test to verify that symbols are available

P.S. I suggest changing the comment in the new test that states "where the function names are available even with no symbols". This is not very accurate, the reason it works is because the symbols are inside libjvm.so itself, unlike with Microsoft Visual C which places all debug information (including symbol names) into the pdb files entirely. (For instance, if you compile the Windows Java VM with gcc, the symbol names would also be inside the VM itself, and not in the debug files)

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PR Comment: https://git.openjdk.org/jdk/pull/16039#issuecomment-1754175834