Latest GIT (April 10, short version 5566) broke building on Slackware 13.1.
Reversing patches 20fc5cd8, ffc39044, and 0f026179 allows building.
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This is to be expected due to your previous tdelibs FTBFS. Rebuilding and installing tdelibs from GIT will provide the missing class declaration.
All is well.
Darrell