Considered change	Motive	S	B
Remove old_size argument from gmp_realloc and gmp_free	cleanness; less confusing interface; very slight speedup	✓	✓
Somehow extend allocation interface to support efficient _mpz_newalloc	performance; useless to have realloc copy data which will not be used	✓	✓
Clean up gmp_randstate_t struct from apparent mpz dependencies, unused fields	cleanness; memory use; allow randstate-based mpn functions		✓
Add return value to mpz_sqrt (analogous to mpz_root)	usefulness	✓
Add return value to mpz_gcd and mpz_gcdext, to indicate if inputs are coprime. Allow null gcd output argument.	usefulness; for usecases which don't care about the actual gcd, e.g., mpz_invert	✓
Clean up *_str functions to forbid spaces	sense
Allow for mpz operands of up to 250 by combining the _mp_size and _mp_alloc fieds into one 64-bit bitfield, encoding _mp_alloc as a custom float.	usefulness	✓	✓
Add unsigned long long functions, mpX_func_uj. (Note that this requires C99 for library compilation, while we should allow user code to be compiled by any C90 compiler but then #define away the uj interfaces.)	usefulness	✓	✓
Consider making mp_bitcnt_t a 64-bit integer also on 32-bit hosts.	avoiding overflow for certain interfaces for otherwise in-range numbers	✓	✓
Consider changing return value for gmp_*printf* from int to long. Likewise, change * width arguments' type.	allow printing of huge numbers while still returning sensible values.	✓	✓