RFR: 8296754: AutoCreateSharedArchive in JDK 20 is not compatible with JDK 19

[Calvin Cheung]

On Mon, 14 Nov 2022 21:33:23 GMT, Matias Saavedra Silva <matsaave at openjdk.org> wrote:

> The -XX:+AutoCreateSharedArchive flag was implemented in JDK 19, however, this flag doesn't work across JDK 19 and 20.
> 
> Expected: JDK 20 should recreate the specified CDS archive
> Actual: JDK 20 cannot recognize the archive file and gives up
> 
> The new field from GenericCDSFileMapHeader is now in FileMapHeader.

Looks good. Just couple of nits.

src/hotspot/share/cds/cdsConstants.cpp line 38:

> 36:   { "GenericCDSFileMapHeader::_version",                   offset_of(GenericCDSFileMapHeader, _version)                  },
> 37:   { "GenericCDSFileMapHeader::_header_size",               offset_of(GenericCDSFileMapHeader, _header_size)              },
> 38:   { "GenericCDSFileMapHeader::_base_archive_name_offset",  offset_of(GenericCDSFileMapHeader, _base_archive_name_offset) },

I think you can delete one space between "," and "offset_of" and also adjust other lines accordingly.

test/hotspot/jtreg/runtime/cds/appcds/test-classes/HelloJDK8.java line 26:

> 24: 
> 25: 
> 26: // Used by tests like dynamicArchive/TestAutoCreateSharedArchive.java, which

s/TestAutoCreateSharedArchive/TestAutoCreateSharedArchiveUpgrade

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Marked as reviewed by ccheung (Reviewer).

PR: https://git.openjdk.org/jdk/pull/11148