512f64289a
Also call out possible exposure of an existing cache entry of the same
name, as we have for the `unset` command since commit 1a0f1a25a4 (Help:
Clarify the unset command, 2018-08-17, v3.13.0-rc1~199^2).
Issue: #24633
10 lines
514 B
Plaintext
10 lines
514 B
Plaintext
.. note::
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When evaluating :ref:`Variable References` of the form ``${VAR}``, CMake
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first searches for a normal variable with that name. If no such normal
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variable exists, CMake will then search for a cache entry with that name.
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Because of this, **unsetting a normal variable can expose a cache variable
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that was previously hidden**. To force a variable reference of the form
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``${VAR}`` to return an empty string, use ``set(<variable> "")``, which
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clears the normal variable but leaves it defined.
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