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From: "redi at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug libstdc++/106275] unordered_map with std::string key,
 std::hash<std::string>, and custom equality predicate weirdness
Date: Tue, 12 Jul 2022 23:00:10 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D106275

--- Comment #5 from Jonathan Wakely <redi at gcc dot gnu.org> ---
This "bug" (i.e. doing a linear search for small containers using slow hash
functions) makes the find operation more than twice as fast:

BM_std_hash          4.67 ns         4.66 ns    150610579
BM_custom_hash       12.0 ns         12.0 ns     57529241

See PR 68303 for more details.=