boehm-gc: update to 7.6.8.

== [7.6.8] 2018-08-12 ==

* Add cpu, make_as_lib, nothreads options to NT_MAKEFILE
* Add NetBSD/aarch64 and initial RISC-V support
* Adjust formatting of configure help messages and config.h comments
* Avoid multiple 'getcontext failed' warnings if getcontext is broken
* Cleanup BCC Makefile (remove absolute GC paths, fix del cmd, update clean)
* Collapse multiple NT_*_MAKEFILE scripts into a single NT_MAKEFILE
* Do not call GC_dirty_inner unless GC_incremental
* Do not use NULL in gc_inline.h
* Eliminate 'cast between incompatible function types' compiler warning
* Eliminate 'comparing signed and unsigned values' compiler warnings (bcc)
* Eliminate 'condition is always true' cppcheck warning in init_gcj_malloc
* Eliminate 'declaration of var hides global declaration' compiler warning
* Eliminate 'language extension used' Clang warning in gc.h
* Eliminate 'possibly incorrect assignment in CORD_vsprintf' compiler warning
* Eliminate 'ptr arithmetic with NULL' cppcheck warning in alloc_mark_stack
* Eliminate 'scope of var can be reduced' cppcheck warning in pthread_join
* Eliminate 'switch statement contains no case label' compiler warning
* Eliminate 'variable might be uninitialized' warning in win32_start_inner
* Eliminate duplicate clear_mark_bit call when removing disappearing link
* Fast fail on invalid CPU parameter passed to NT_MAKEFILE
* Fix 'collecting from unknown thread' abort in leak-finding mode
* Fix 'pointer arithmetic with NULL' code defect in print_callers
* Fix Borland version in documentation to match that in BCC_MAKEFILE
* Fix comment about inv_sz computation in setup_header
* Fix comments style in configure.ac and Makefile.am
* Fix compilation by digimars.mak (DMC)
* Fix compilation by WCC makefile
* Fix compilation of darwin_stop_world for iOS 8+
* Fix cords for MANUAL_VDB
* Fix dependency on gc_cpp source in BCC_MAKEFILE and NT_MAKEFILE
* Fix GC_is_valid_displacement and GC_is_visible for non-small objects
* Fix gctest in leak-finding mode
* Fix infinite restarting of mark_some when a static root disappeared (Linux)
* Fix large object base computation in PUSH_CONTENTS() if MARK_BIT_PER_OBJ
* Fix mark stack overflow checking in push_selected
* Fix missing GC_dirty calls for GC-allocated objects used internally
* Fix missing GC_dirty invocation from debug_end_stubborn_change
* Fix MSWIN32 macro redefinition (WCC)
* Fix multi-threaded gctest for the case of NTHREADS is set to zero
* Fix new and delete operators definition for DigitalMars compiler
* Fix NT_MAKEFILE for VS 2017
* Fix potential null dereference in GC_CONS
* Fix register_dynamic_libraries on Windows 10
* Fix result computation in n_set_marks
* Fix return type in GC_set_warn_proc API documentation
* Fix tests for GC compiled with MANUAL_VDB
* Fix the build for Emscripten
* Fix typo in comment for CORD_ec_flush_buf prototype
* Fix typos in ChangeLog and generic_malloc
* Fix UNTESTED for multi-threaded API functions in gctest
* Fix VirtualQuery call in case of malloc failure (Win32)
* Install gc.3 man page instead of copying gc.man to doc folder (configure)
* Keep pointer to the start of previous entry in remove_specific_after_fork
* Move de_win compiled resource files to cord/tests
* Never return null by C++ GC allocators and gc_cpp operator new
* Perform thread_suspend in loop as it may be interrupted (Darwin)
* Really abort if failed to read /proc for library registration (Linux)
* Remove code duplication in gcj_malloc and malloc_explicitly_typed
* Remove duplicate local variable in reclaim_block
* Remove information how to send bugs from README.cords file
* Remove libatomic_ops license information
* Remove unused USE_GENERIC macro definition and description
* Suppress 'functions containing switch are not expanded inline' bcc warning
* Suppress 'non-member operator new/delete may not be inline' VC++ warning
* Turn on incremental collection in gctest also if MANUAL_VDB
* Update copyright information in alloc.c, gc.c/h and the documentation
* Update EXTRA_DIST in Makefile, Win32/64 docs after NT_*_MAKEFILE removal
* Update NT_MAKEFILE usage information in README files for Win32 and Win64
* Workaround 'class C does not have a copy constructor' cppcheck warning
* Workaround 'function nested_sp is never used' cppcheck style warning
* Workaround 'opposite expression on both sides of &' cppcheck style warning
* Workaround 'template-id not supported in this context' compiler error (WCC)

== [7.6.6] 2018-04-20 ==

* Define GC_FREEBSD_THREADS and GC_ADD_CALLER macros for kFreeBSD
* Eliminate 'boolean result used in bitwise operation' cppcheck warning
* Eliminate 'there is pointer arithmetic with NULL' cppcheck warning
* Explicitly unblock GC signals on GC initialization
* Fix 'scope of var can be reduced' cppcheck err in enqueue_all_finalizers
* Fix 'undefined reference to __builtin_unwind_init' linker error (ArmCC)
* Fix arguments delimiter in pcr_interface.c (PCR)
* Fix assertion violation in DllMain of win32_threads
* Fix comment for debug_generic_malloc_inner[_ignore_off_page]
* Fix data race during apply_to_each_object(reset_back_edge)
* Fix dbg_mlc.c/o file name in documentation
* Fix gctest with musl libc on s390x
* Fix include gc_gcj.h in thread_local_alloc.c
* Fix man section number (3)
* Fix missing GC_generic_malloc_words_small implementation in new_gc_alloc.h
* Fix missing new-line in ABORT_ARG<n> definition
* Fix missing SIGBUS handler setup for kFreeBSD
* Fix null dereference in print_callers on backtrace_symbols failure
* Fix null pointer dereference in get_private_path_and_zero_file (Symbian)
* Fix the collector hang when it is configured with --enable-gc-debug
* Fix thread_suspend fail for threads registered from key destructor (OS X)
* Fix type of local variables receiving result of PHT_HASH
* Fix typo in AIX macro name
* Fix typo in comment in specific.h
* Fix unbounded heap growth in case of intensive disappearing links usage
* Remove API symbols renaming in WCC_MAKEFILE
* Support Haiku/amd64 and Haiku/x86 hosts
* Support threads for DragonFly in configure
* Workaround 'address of auto-variable returned' cppcheck error
* Workaround gctest hang on kFreeBSD (if thread-local allocations are on)


(wiz)