a1c2882d72
This Error can be returned from operations on JITDylibs that cannot proceed as the target JITDylib has been closed. This patch uses the new error to replace an unsafe assertion in JITDylib::define: If a JITDylib::define operation is run by an in-flight task after the target JITDylib is closed it should error out rather than asserting. See also https://github.com/llvm/llvm-project/issues/174922