From cppreference.com
Indicates that the function definition should be optimized for invocation from a
.
Syntax
[[optimize_for_synchronized]]Explanation
Applies to the name being declared in a function declaration, which must be the first declaration of the function.
Indicates that the function definition should be optimized for invocation from a
. In particular, it avoids serializing synchronized blocks that make a call to a function that is transaction-safe for the majority of calls, but not for all calls.
Example
References
Transactional Memory TS (ISO/IEC TS 19841:2015):
7.6.6 Attribute for optimization in synchronized blocks [dcl.attr.sync]