There's a merged pull request on the void-packages repository

jdupes: update to 1.21.0.
https://github.com/void-linux/void-packages/pull/40361

Description:
CFLAGS="-DENABLE_DEDUPE" is enough to enable --dedupe. See a92952dbd0aaa34b72792c362f002e9f19a3d84c and #32048.

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