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diff --git a/share/cmake-3.17/Help/policy/CMP0012.rst b/share/cmake-3.17/Help/policy/CMP0012.rst new file mode 100644 index 0000000..17ec8d3 --- /dev/null +++ b/share/cmake-3.17/Help/policy/CMP0012.rst @@ -0,0 +1,28 @@ +CMP0012 +------- + +:command:`if` recognizes numbers and boolean constants. + +In CMake versions 2.6.4 and lower the :command:`if` command implicitly +dereferenced arguments corresponding to variables, even those named +like numbers or boolean constants, except for ``0`` and ``1``. Numbers and +boolean constants such as ``true``, ``false``, ``yes``, ``no``, ``on``, +``off``, ``y``, ``n``, ``notfound``, ``ignore`` (all case insensitive) +were recognized in some cases but not all. For example, the code ``if(TRUE)`` +might have evaluated as ``false``. +Numbers such as 2 were recognized only in boolean expressions +like ``if(NOT 2)`` (leading to ``false``) but not as a single-argument like +``if(2)`` (also leading to ``false``). Later versions of CMake prefer to +treat numbers and boolean constants literally, so they should not be +used as variable names. + +The ``OLD`` behavior for this policy is to implicitly dereference +variables named like numbers and boolean constants. The ``NEW`` behavior +for this policy is to recognize numbers and boolean constants without +dereferencing variables with such names. + +This policy was introduced in CMake version 2.8.0. CMake version +|release| warns when the policy is not set and uses ``OLD`` behavior. Use +the :command:`cmake_policy` command to set it to ``OLD`` or ``NEW`` explicitly. + +.. include:: DEPRECATED.txt |