libgcc/:
* generic-morestack.c: Include <string.h>.
(uintptr_type): Define.
(struct initial_sp): Add dont_block_signals field. Reduce size of
extra array by 1.
(allocate_segment): Set prev field to NULL. Don't set
__morestack_current_segment or __morestack_segments.
(__generic_morestack): Update current->prev and *pp after calling
allocate_segment.
(__morestack_block_signals): Don't do anything if
dont_block_signals is set.
(__morestack_unblock_signals): Likewise.
(__generic_findstack): Check for initial_sp == NULL. Add casts to
uintptr_type.
(__splitstack_block_signals): New function.
(enum __splitstack_content_offsets): Define.
(__splitstack_getcontext, __splitstack_setcontext): New functions.
(__splitstack_makecontext): New function.
(__splitstack_block_signals_context): New function.
(__splitstack_find_context): New function.
* config/i386/morestack.S (__morestack_get_guard): New function.
(__morestack_set_guard, __morestack_make_guard): New functions.
* libgcc-std.ver.in: Add new functions to GCC_4.7.0.
gcc/testsuite/:
* lib/target-supports.exp (check_effective_target_ucontext_h): New
procedure.
* gcc.dg/split-5.c: New test.
From-SVN: r181234
e14304eff5