https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98049
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
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Last reconfirmed|2020-11-30 00:00:00 |2021-4-9
Known to fail| |10.2.0, 11.0
CC| |msebor at gcc dot gnu.org
--- Comment #2 from Martin Sebor <msebor at gcc dot gnu.org> ---
The false positive is due to the algorithm exceeding the hardcoded conservative
internal MAX_CHAIN_LEN limit. Bumping it up from the current 5 to 6 avoids the
warning in this case.
As far as I can tell, the limit keeps the algorithm from becoming O(n^2) while
detecting cycles in the dependency graph. But it looks to me like we might be
able to achieve the same result by using a more efficient data structure, such
as bitmap rather than iterating over the elements of a vector (the edges of the
graph).
