RFR: 8307569: Build with gcc8 is broken after JDK-8307301

[Jie Fu]

The fix disables expansion-to-defined warning for gcc.
Thanks.

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Commit messages:
 - 8307569: Build with gcc8 is broken after JDK-8307301

Changes: https://git.openjdk.org/jdk/pull/13850/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=13850&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8307569
  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/13850.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/13850/head:pull/13850

PR: https://git.openjdk.org/jdk/pull/13850