racy
adj.adj. describing code that has a race condition, where two or more parts of a program try to change the same data at the same time. This can cause the program to behave in an unexpected or dangerous way.
adj. characterised by a race condition, where the outcome of a program depends on the relative timing of events. Often used in the context of concurrent or parallel programming to describe code that is not thread-safe.
The developer found a racy condition in the login system.
Because the two threads are accessing the same memory address without a lock, the code is racy and may crash under heavy load.
While the single-threaded version of the algorithm worked perfectly, the multi-threaded implementation was racy, leading to inconsistent data states that were difficult to reproduce during testing.
From race (“having a characteristic taste (of wines, fruits, etc.)”) + -y.