Allow multiple calls to REFLEX_GENERATE_DICTIONARY

[Dr15Jones]

Explain what you would like to see improved and how.

The CMake function REFLEX_GENERATE_DICTIONARY can only be called once for each CMake target as it generates a file based on the target name.

In CMS code, we allow multiple classes_def*.xml files for each library being created. This has sped up compilation and avoids excessing memory use by the compiler. Because of the restriction in REFLEX_GENERATE_DICTIONARY , my experiments to use CMake to generate some CMSSW code was unable to use that function.

It appears that if REFLEX_GENERATE_DICTIONARY used part of the name of the SELECTION argument for the generate class name it could be possible to have multiple calls to the function for the same target.

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Installation method

from source

Operating system

Linux alma 8

Additional context

No response