In Hungarian, all consonants have long and short versions, and there are many minimal pairs. Examples:
pára /paːrɒ/ "fog/steam/condensation" | párra /paːrːɒ/ "onto the pair"
vére /veːrɛ/ "his blood" | vérre /veːrːɛ/ "to blood"
ara /ɒrɒ/ "macaw" | arra /ɒrːɒ/ "that way"
According to Wikipedia, Slovak does contrast /r/ and /rː/, but the Journal of IPA on Slovak says that the geminated /r/ (i.e. /rː/) is considered an allophone of /r/ because there are no minimal pairs of /r/ and /rː/. They're not in complementary distribution: the geminated /r/ ‘can only occur in the syllable nucleus’, the short /r/ ‘in the nucleus and ...
(Due to finding a source that I think provides an even better example than my previous answer, I've updated this post).
In “Initial and Medial Geminate Trills in Arop-Lokep,” by Raymond, Mary, and Steve Parker (Journal of the International Phonetic Association, vol. 35, no. 1, 2005, pp. 99–111. JSTOR, www.jstor.org/stable/44526399. Accessed 17 ...
In many dialects of Pashto, xʷ only occurs in clusters. It only occurs in clusters (mostly before [r ~ ɾ] and [l]). It never occurs alone and contrasts with x (and xw in some words) for example /xre/ means “(you're a) female donkey” and /xʷre/ [with rising intonation] means “(are you) eating?”. Some other examples and minimal pairs are:
[xʷrɐm] “(I am) ...