RFR: 8305341: Alignment should be enforced by alignas instead of compiler specific attributes [v6]

[Julian Waters]

> C11 has been stable for a long time on all platforms, so native code can use the standard alignas operator for alignment requirements

Julian Waters has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 18 commits:

 - Merge branch 'openjdk:master' into patch-6
 - Whitespace
 - Revert
 - _MSC_VER
 - Restore visCPP
 - Restore gcc attribute
 - Revert gcc
 - Revert
 - Semicolon
 - gcc offset_of
 - ... and 8 more: https://git.openjdk.org/jdk/compare/5a82fa3b...6c289fb3

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Changes: https://git.openjdk.org/jdk/pull/13258/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13258&range=05
  Stats: 11 lines in 3 files changed: 5 ins; 0 del; 6 mod
  Patch: https://git.openjdk.org/jdk/pull/13258.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13258/head:pull/13258

PR: https://git.openjdk.org/jdk/pull/13258