And even worse, it's not as if it wasn't explicitly specified in the code (https://github.com/slimcoin-project/Slimcoin/blob/master/src/util.h#L90) ...
#define PRI64d  "lld"
#define PRI64u  "llu"
#define PRI64x  "llx"

Sigh. Aaanyway, I revisited the original committed changes and ensured that each was appropriately longlonged: https://github.com/slimcoin-project/Slimcoin/commit/aaf3e387d39a1371c15adc811afdf0417246f22e

Cheers

Graham