ZOOKEEPER-3954: C client: GCC 10 compilation fixes #1487
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…ining Michael Hudson-Doyle experienced an error while compiling the C client with GCC 10 and aggressive optimization settings: > `free_auth_completions` is being inlined into `free_completions`, > and this lets gcc see that members of `a_list` are being accessed > without initialization This is (fortunately!) a red herring: what GCC doesn't see is that, in practice, `zoo_lock_auth` always returns zero, and that `a_list` is always initialized in the conditional block which follows it. Let's "fix" this by removing the `if`. The rest of the client code doesn't check `zoo_lock_auth`'s return value--and we have bigger issues if unconditional locks start failing anyway.
ztzg
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I'm going to merge this PR, plus the others open for branch-3.6 and 3.5) |
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Ok for all of them |
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Thanks! |
RokLenarcic
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The in this PR avoids a confusing and scary compilation issue [encountered by Michael Hudson-Doyle](https://issues.apache.org/jira/browse/ZOOKEEPER-3954) when building the C client with GCC 10 and "aggressive" optimization settings: > `free_auth_completions` is being inlined into `free_completions`, and this lets gcc see that members of `a_list` are being accessed without initialization This is (fortunately!) a red herring: what GCC doesn't see is that, in practice, `zoo_lock_auth` always returns zero, and that `a_list` is always initialized in the conditional block which follows it. That issue is easily "fixed" by removing the `if`. The rest of the client code doesn't check `zoo_lock_auth`'s return value--and we have bigger issues if unconditional locks start failing anyway. See also apache#1481 and apache#1486. Author: Damien Diederen <dd@crosstwine.com> Reviewers: Enrico Olivelli <eolivelli@apache.org>, Mate Szalay-Beko <symat@apache.org> Closes apache#1487 from ztzg/ZOOKEEPER-3954-gcc10-compilation-fixes-master
RokLenarcic
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Aug 31, 2022
The in this PR avoids a confusing and scary compilation issue [encountered by Michael Hudson-Doyle](https://issues.apache.org/jira/browse/ZOOKEEPER-3954) when building the C client with GCC 10 and "aggressive" optimization settings: > `free_auth_completions` is being inlined into `free_completions`, and this lets gcc see that members of `a_list` are being accessed without initialization This is (fortunately!) a red herring: what GCC doesn't see is that, in practice, `zoo_lock_auth` always returns zero, and that `a_list` is always initialized in the conditional block which follows it. That issue is easily "fixed" by removing the `if`. The rest of the client code doesn't check `zoo_lock_auth`'s return value--and we have bigger issues if unconditional locks start failing anyway. See also apache#1481 and apache#1486. Author: Damien Diederen <dd@crosstwine.com> Reviewers: Enrico Olivelli <eolivelli@apache.org>, Mate Szalay-Beko <symat@apache.org> Closes apache#1487 from ztzg/ZOOKEEPER-3954-gcc10-compilation-fixes-master
RokLenarcic
pushed a commit
to RokLenarcic/zookeeper
that referenced
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Aug 31, 2022
The in this PR avoids a confusing and scary compilation issue [encountered by Michael Hudson-Doyle](https://issues.apache.org/jira/browse/ZOOKEEPER-3954) when building the C client with GCC 10 and "aggressive" optimization settings: > `free_auth_completions` is being inlined into `free_completions`, and this lets gcc see that members of `a_list` are being accessed without initialization This is (fortunately!) a red herring: what GCC doesn't see is that, in practice, `zoo_lock_auth` always returns zero, and that `a_list` is always initialized in the conditional block which follows it. That issue is easily "fixed" by removing the `if`. The rest of the client code doesn't check `zoo_lock_auth`'s return value--and we have bigger issues if unconditional locks start failing anyway. See also apache#1481 and apache#1486. Author: Damien Diederen <dd@crosstwine.com> Reviewers: Enrico Olivelli <eolivelli@apache.org>, Mate Szalay-Beko <symat@apache.org> Closes apache#1487 from ztzg/ZOOKEEPER-3954-gcc10-compilation-fixes-master
RokLenarcic
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Sep 3, 2022
The in this PR avoids a confusing and scary compilation issue [encountered by Michael Hudson-Doyle](https://issues.apache.org/jira/browse/ZOOKEEPER-3954) when building the C client with GCC 10 and "aggressive" optimization settings: > `free_auth_completions` is being inlined into `free_completions`, and this lets gcc see that members of `a_list` are being accessed without initialization This is (fortunately!) a red herring: what GCC doesn't see is that, in practice, `zoo_lock_auth` always returns zero, and that `a_list` is always initialized in the conditional block which follows it. That issue is easily "fixed" by removing the `if`. The rest of the client code doesn't check `zoo_lock_auth`'s return value--and we have bigger issues if unconditional locks start failing anyway. See also apache#1481 and apache#1486. Author: Damien Diederen <dd@crosstwine.com> Reviewers: Enrico Olivelli <eolivelli@apache.org>, Mate Szalay-Beko <symat@apache.org> Closes apache#1487 from ztzg/ZOOKEEPER-3954-gcc10-compilation-fixes-master
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The in this PR avoids a confusing and scary compilation issue encountered by Michael Hudson-Doyle when building the C client with GCC 10 and "aggressive" optimization settings:
This is (fortunately!) a red herring: what GCC doesn't see is that, in practice,
zoo_lock_authalways returns zero, and thata_listis always initialized in the conditional block which follows it.That issue is easily "fixed" by removing the
if. The rest of the client code doesn't checkzoo_lock_auth's return value--and we have bigger issues if unconditional locks start failing anyway.See also #1481 and #1486.