RFR: 8266168: -Wmaybe-uninitialized happens in check_code.c

[Yasumasa Suenaga]

We can see following compiler warning in check_code.c on GCC 11.

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Commit messages:
 - 8266168: -Wmaybe-uninitialized happens in check_code.c

Changes: https://git.openjdk.java.net/jdk/pull/3787/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=3787&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8266168
  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/3787.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/3787/head:pull/3787

PR: https://git.openjdk.java.net/jdk/pull/3787