Al Kelley <blufox@ucsc.edu> writes: > > ld: fatal: file .../gnu/lib/libgmpxx.so: wrong ELF class: ELFCLASS64 By default gmp builds for the 64-bit ABI, because it gives faster code. You need to add corresponding options when compiling your program. See "ABI and ISA" in the manual. PS. Bug reports to bug-gmp@gnu.org please.