A UMC message indicates that an uninitialized value is being copied from one memory location to another. Such copies are normally harmless. They occur, for example, when padding fields in structures are copied.
For instance, Purify reports a UMC message when you:
§ Use memcpy() to copy uninitialized data
§ Use the REP MOVS machine instruction to copy uninitialized data
Note:
§ By default, Purify does not record UMC messages. You can turn on recording to help track down sequences of copies that lead to an apparently initialized variable containing uninitialized data. This generates an Uninitialized Memory Read (UMR) when you use the data. To display UMC messages, select Show UMC messages in the Errors and Leaks tab in the settings dialog boxes.
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