RFR: 8263718: unused-result warning happens at os_linux.cpp

[Yasumasa Suenaga]

I tried to build OpenJDK with g++-10.2.1_pre1-r3 on Alpine Linux 3.13.2, but I saw following warning:


  668 | alloca(((pid ^ counter++) & 7) * 128);
      | ^
cc1plus: all warnings being treated as errors

-------------

Commit messages:
 - 8263718: unused-result warning happens at os_linux.cpp

Changes: https://git.openjdk.java.net/jdk/pull/3042/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3042&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8263718
  Stats: 11 lines in 3 files changed: 9 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3042.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3042/head:pull/3042

PR: https://git.openjdk.java.net/jdk/pull/3042