Log Message:
== [7.4.6] 2017-05-18 ==

* Add assertion that double-wide CAS target is aligned (msftc/x86[_64])
* Add configure --enable-gcov option (enable code coverage analysis)
* Code refactoring of gcc/powerpc.h to avoid code duplication
* Eliminate 'cast to long from void*' compiler warning in test_atomic
* Eliminate 'implicit declaration of close' warning in 'strict ANSI' mode
* Eliminate 'missing braces around initializer' gcc warning (hppa)
* Eliminate 'printf format specifies type void*' GCC pedantic warnings
* Eliminate 'value shift followed by expansion' false code defect warning
* Enable limited testing in Makefile.msft without Cygwin
* Fix (delete) comment for AO_and_full (x86)
* Fix block_all_signals compilation in 'strict ANSI' mode
* Fix missing .exe for test filenames in Makefile (MinGW)
* Fix missing printed value names (test_stack)
* Implement fetch-CAS for s390[x] (gcc)
* Move libraries version info to the beginning of Makefile.am
* Refine documentation in Makefile.msft how to run all tests (MS VC)
* Refine README about library downloading
* Rename doc/README.txt to doc/README_details.txt
* Support AIX/ppc (gcc)
* Support CFLAGS_EXTRA to pass extra user-defined compiler flags (make)
* Support n32 ABI for mips64
* Update shared libraries version info for 7.4.6+ (to 1:4:0)
* Use 'inline code' format for commands in README.md
* Use LLD and SCD instructions on mips64
* Workaround 'resource leak' false positives in AO_malloc, add_elements
* Workaround 'uninitialized memory use' MemorySanitizer warning (test_atomic)
Also, includes 7.2h changes