[C++] UBSAN error "applying non-zero offset to null pointer"

[asfimport]

Clang's ubsan considers a non-zero offset being added to a null pointer to be undefined behavior.  This causes ubsan violations in our test suites if you are using clang-10 or higher.

This was not detected by CI since CI uses clang-8 and this check was added in clang-10 [1][2].

 

 [1] https://reviews.llvm.org/D67122

 [2] https://releases.llvm.org/10.0.0/tools/clang/docs/ReleaseNotes.html#undefined-behavior-sanitizer-ubsan

 

Reporter: Weston Pace / @westonpace
Assignee: Weston Pace / @westonpace

PRs and other links:

• GitHub Pull Request #10787
• GitHub Pull Request #10795

_{Note: This issue was originally created as ARROW-13440. Please see the migration documentation for further details.}

[asfimport]

Antoine Pitrou / @pitrou:
Is this fixed or not? The linked PRs don't seem very informative.

[asfimport]

Antoine Pitrou / @pitrou:
@westonpace  What is the status on this?

[asfimport]

Weston Pace / @westonpace:
This was fixed incidentally as part of ARROW-13444

[asfimport]

Weston Pace / @westonpace:
Thanks for bringing it to my attention