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It should be a simple matter to build a dependency tree from the entries in the Import command.
SCons going off and trying to build libraries from an upstream
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package if that package build has already failed.
I think this is a non-issue. I have looked into writing an SConstruct file that will stop the build of the application if a library it needs does not already exist. Unfortunately, because SCons reads and processes all of the SConscript files before trying to build anything, the best I could do was disable the building of the application entirely, such that no build failure is registered as it would be if there were a simply a missing library. Maybe this is ok, but it is not how the present RM works.
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