Updated libatomic_ops to 7.6.0.

== [7.6.0] 2017-05-19 ==

* Add *_and/or/xor* and *_[fetch_]compare_and_swap* tests to test_atomic
* Add asm-based and/or/xor implementation for char/short/int (gcc/x86)
* Add asm-based char/short/int CAS implementation for gcc/x86[_64]
* Add configure '--disable-atomic-intrinsics' option
* Add dd_acquire_read case to test_atomic
* Add initial nios2 architecture support
* Add Makefile target (check-nolink) to compile all source without linking
* Add Makefile target to run all tests without test-driver
* Add test_atomic_generalized to Makefile and Makefile.msft
* Allow alternate CC (CROSS_CC) for AC_TRY_COMPILE (configure)
* Always define word-wide CAS for x86 (MS VC++ 8+)
* Avoid atomic_compare_exchange_n if no __GCC_HAVE_SYNC_COMPARE_AND_SWAP_n
* Avoid extra nop_full in stack_pop_acquire if atomic intrinsics used (x86)
* Basic support of TILE-Gx and TILEPro CPUs
* Code refactoring of int-wide primitives in gcc/x86.h
* Define AO_TS_SET as __GCC_ATOMIC_TEST_AND_SET_TRUEVAL if applicable
* Define CLANG/GNUC_PREREQ macros to check gcc/clang minimum version
* Do not define print_list() unless used (tests)
* Eliminate 'condition sizeof(long)>4 is always true' cppcheck style warning
* Eliminate 'ISO C90 does not support long long' compiler pedantic warning
* Eliminate 'scope of variable can be reduced' cppcheck warnings
* Eliminate redundant lwsync 2nd call in CAS_full on fail (gcc/PowerPC)
* Fix 'unknown attribute no_sanitize' compiler warning (clang prior to v3.8)
* Fix 'variable new value is never used' cppcheck style warning
* Fix missing double_compare_and_swap_dd_acquire_read
* Fix reporting about missing and/or/xor_dd_acquire_read (test_atomic)
* Hide AO_locks symbol
* Implement AO_CLEAR using C11 atomic intrinsic (GCC)
* Implement CAS_acquire/release/full using __atomic_compare_exchange_n (gcc)
* Implement char and/or/xor and short CAS for msftc ARM and X86[_64]
* Implement char CAS and char/short add for msftc X86[_64] (VS 2013+)
* Implement compiler_barrier using C11 __atomic_signal_fence (GCC)
* Implement int CAS/inc/dec for msftc/x86_64
* Implement short inc/dec directly for msftc ARM and X86[_64]
* Initial ibmc/powerpc (xlc) support
* New configure option (--enable-werror) to treat warnings as compiler errors
* New macro AO_PREFER_BUILTIN_ATOMICS to rely on C11 atomics fully (AArch64)
* Refine AO_nop_write comment for ARM big.LITTLE architecture
* Refine configure messages when checking for compiler options
* Refine documentation about _full memory ordering suffix
* Refine README how to build the library source from the repository
* Relax shareability domain for dmb st in AO_nop_write (ARM/AArch64)
* Remove redundant include windows.h from headers (msftc/x86[_64])
* Remove spaces at EOLn in asm code
* Report gcc/clang pedantic warnings (configure)
* Support NaCl/arm
* Suppress 'ISO C does not support __int128 type' GCC/Clang pedantic warning
* Test store/CAS emulation explicitly
* Update shared libraries version info to 2:0:1
* Use GCC atomic intrinsics for PowerPC 32/64 (GCC 4.8+ and clang 3.8+)
* Use GCC atomic intrinsics for x86, x64, ARM, MIPS (gcc 4.9+, clang 3.5+)
* Use generalized double-wide load/store if AO_PREFER_GENERALIZED (gcc/x86)
* Workaround '#error' cppcheck error messages
* Workaround 'condition always true', 'unused stored value' cppcheck warnings
* Workaround 'function is never used' cppcheck style warnings
* Workaround 'obsolescent ftime called' cppcheck style warning (POSIX)
* Workaround 'overflow in pointer subtraction' cppcheck warning
* Workaround 'shifting 32-bit value by 32 bits undefined' cppcheck warning
* Workaround 'uninitialized memory use' code analyzer false warning (tests)
* Workaround 'uninitialized variable' cppcheck error in hpc/hppa.h
* Workaround 'value of macro is unknown' cppcheck information messages
* Workaround a bug in double-wide intrinsics of Clang/x64 with ASan enabled
* Workaround MSan warning about uninitialized data read by generalized store


(wiz)