[jdk17u-dev] RFR: 8307569: Build with gcc8 is broken after JDK-8307301

[Goetz Lindenmaier]

I backport this for parity with 17.0.9-oracle.

I had to resolve, In 17, there are much more warnings disabled.

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Commit messages:
 - Backport 64c09628664fd19c281723f15bf677c52e360acd

Changes: https://git.openjdk.org/jdk17u-dev/pull/1466/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk17u-dev&pr=1466&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8307569
  Stats: 3 lines in 1 file changed: 2 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk17u-dev/pull/1466.diff
  Fetch: git fetch https://git.openjdk.org/jdk17u-dev.git pull/1466/head:pull/1466

PR: https://git.openjdk.org/jdk17u-dev/pull/1466