On Tue, 18 Apr 2023 22:25:09 GMT, Maurizio Cimadamore <mcimadam...@openjdk.org> wrote:
>> Jorn Vernee has updated the pull request with a new target base due to a >> merge or a rebase. The incremental webrev excludes the unrelated changes >> brought in by the merge/rebase. The pull request contains seven additional >> commits since the last revision: >> >> - fix TestIllegalLink >> - Merge branch 'PR_21' into RejectPacked >> - Merge branch 'PR_21' into RejectPacked >> - add javadoc + fixes for trailing padding >> - fix check for padding. Add check for trailing padding too >> - Reject packed structs and structs with extra padding >> - Check byte order of layouts passed to linker > > src/java.base/share/classes/java/lang/foreign/Linker.java line 202: > >> 200: * Due to limited ABI specification coverage, all the native linker >> implementations limit the function >> 201: * descriptors that they support to those that contain only so-called >> <em>canonical</em> layouts. These layouts >> 202: * have the following restrictions: > > I think it's better to phrase this more or less as: > > A canonical layout has the following characteristics: > * Its alignment constraint is equal to its natural alignment > * If the layout is a value layout (linkplain), its byte order matches that of > the platform in which the JVM is executing (link to nativeOrder()) > * If the layout is a group layout (linkplain), it must not contain more > padding layout (linkplain) elements than those strictly necessary to satisfy > the alignment constraints of the non-padding elements of the group layout. Also, isn't it the case that, for structs, we want the size of the layout to be a multiple of its alignment constraint? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/13164#discussion_r1170624776
