E2189 Thread local variables cannot be local to a function (Delphi)
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Thread local variables must be declared at a global scope.
program Produce; procedure NoTLS; threadvar x : Integer; begin end; begin end.
A thread variable cannot be declared local to a procedure.
program Solve; threadvar x : Integer; procedure YesTLS; var localX : Integer; begin end; begin end.
There are two simple alternatives for avoiding this error. First, the threadvar section can be moved to a local scope. Secondly, the threadvar in the procedure could be changed into a normal var section. Note that if compiler hints are turned on, a hint about localX being declared but not used will be emitted.