CMake Property + Generator expression to get all dependent libraries?

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Is there any way to get the list of all dependent libraries for a target, including transitive dependencies, via a generator expression? The Target property INTERFACE_LINK_LIBRARIES says it includes transitive dependencies, but in my testing, that didn’t seem to be the case.

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CMake doesn’t have generator expression that will give you the complete list of dependent targets.

A generator expression that provided this would require a significant change in how generator expressions are evaluated and introduce new context sensitive rules. Consider a generator expression that does

  • Adds target B if not target A is in the dependent list
  • Adds target A if any other target is in the dependent list

The result of dependent list now changes depending where we are in the evaluation of a generator expression, and now is context sensitive.

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Ah, that’s a good point. That’s too bad. Thanks!

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I saw the new cmake_langauge(DEFER ...) command in CMake 3.19, and I thought maybe I could use that to get a good approximation. Sure, I can’t follow generator expressions, but could at least get those explicitly defined dependencies.

However, it looks like I probably can’t run a cmake script using that, at least in the context of the generator process. Is that right?

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Oh, looks like maybe I’m misunderstanding <command>. I had interpreted that to mean an executable of some sorts, but it looks like it’s actually a cmake function or macro? That is kind of confusing, imo - I think “command” is typically used in CMake to refer to things like running executables, such as in add_custom_target and and_custom_command.

EDIT: I’m mistaken, command is used all the time. Regardless, I wish there was some clarity in this documentation about that.

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You are correct. It might make sense for the command documentation to be <cmake_command>

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