GMP 6.1 is upwardly source and binary compatible with 6.0, 5.1, 5.0, 4.x, and 3.x, except for applications that use the semi-documented mpn_bdivmod function.

Changes in GMP 6.1.2

BUGS FIXED

• Mini-GMP: Fixed a division bug, which on a machine with 64-bit unsigned long affects approximately 1 out of 2³² divisors.
• Mini-GMP: Fix mpz_set_str crash on inputs with a large number of leading zeros. Also stricter input validation, rejecting inputs with no digits.

FEATURES

• Handle more systems which require PIC code in static libraries (e.g., "hardened" Gentoo and Debian 9).
• Configuration for arm (-32 and -64) has been rewritten, fixing poor code selection for many CPUs.
• Mini-GMP: Updated to the latest development version, including new functions mpn_com and mpn_neg.

SPEEDUPS

• None, except for arm CPUs affected by the configuration rewrite.

Changes in GMP 6.1.1

BUGS FIXED

• Make Intel Broadwell configurations work on Windows.

FEATURES

• Work around faulty cpuid on some recent Intel chips (this allows GMP to run on Skylake Pentiums).
• Support thumb-less ARM chips.

Changes in GMP 6.1.0

GMP 6.1.0 release announcement

BUGS FIXED

• The public function mpn_com is now correctly declared in gmp.h.
• Healed possible failures of mpn_sec_sqr for non-cryptographic sizes for some obsolete CPUs.
• The option --disable-assembly now disables all inlined asm.
• Fixed bug affecting mini-gmp's bitwise functions mpz_setbit, mpz_clrbit, and mpz_combit.
• Various problems related to precision for mpf have been fixed.
• Fixed ABI incompatible stack alignment in calls from assembly code.
• Fixed PIC bug in popcount affecting Intel processors using the 32-bit ABI.

SPEEDUPS

• Speedup for Intel Broadwell and Skylake through assembly code making use of new ADX instructions.
• Square root is now faster when the remainder is not needed. Also the speed to compute the k-th root improved, for small sizes.
• Improved arm64 support.

FEATURES

• New C++ functions gcd and lcm for mpz_class.
• New public mpn functions mpn_divexact_1, mpn_zero_p, and mpn_cnd_swap.
• New public mpq_cmp_z function, to efficiently compare rationals with integers.
• Support for Darwin in all x86 code, thereby enabling fat builds on Darwin.
• Support for more 32-bit arm processors.
• Support for compilation with clang/llvm on more platforms. Caution: GMP triggers mis-compilation bugs in clang for many platforms, such as arm, x86 (32-bit and 64-bit), powerpc, mips.
• Support for AVX-less modern x86 CPUs. (Such support might be missing either because the CPU vendor chose to disable AVX, or because the running kernel lacks AVX context switch support.)
• Stack usage trimmed; we believe 512 KiB is now sufficient for any GMP call, irrespective of operand size.
• Support for NetBSD under Xen; we switch off AVX unconditionally under NetBSD since a bug in NetBSD makes AVX fail under Xen.

MISC

• We now use manufacturers' code names for x86 CPUs, e.g., "haswell" instead of names derived from the commercial brands.
• Small improvements and better coverage for the test suite.
• The various FreeBSD problems listed for 6.0.0 affect this release too.
• Tuned values for FFT multiplications are provided for larger number on many platforms.

This release would not have been possible without the continuous work of improvement, revision and refinement by the whole GMP team: Torbjörn Granlund, Niels Möller, Marco Bodrato, and Marc Glisse.
Please see the GMP manual for a complete list of GMP contributors.

There is a public repository for GMP, please see the GMP repository usage instructions for more information.