libsanitizer merge from upstream r250806, compiler part.

gcc/

	* asan.c (asan_emit_stack_protection): Don't pass local stack to
	asan_stack_malloc_[n] anymore. Check if asan_stack_malloc_[n] returned
	NULL and use local stack than.
	(asan_finish_file): Insert __asan_version_mismatch_check_v[n] call
	in addition to __asan_init.
	* sanitizer.def (BUILT_IN_ASAN_INIT): Rename to __asan_init.
	(BUILT_IN_ASAN_VERSION_MISMATCH_CHECK): Add new builtin call.
	* asan.h (asan_intercepted_p): Handle new string builtins.
	* ubsan.c (ubsan_use_new_style_p): New function.
	(ubsan_instrument_float_cast): If location is unknown, assign
	input_location to loc. Propagate loc to ubsan_create_data if
	ubsan_use_new_style_p returned true.

config/

	* bootstrap-asan.mk: Replace ASAN_OPTIONS=detect_leaks with
	LSAN_OPTIONS=detect_leaks.

gcc/testsuite/

	* c-c++-common/ubsan/float-cast-overflow-10.c: Adjust test.
	* c-c++-common/ubsan/float-cast-overflow-8.c: Likewise.
	* c-c++-common/ubsan/float-cast-overflow-9.c: Likewise.
	* g++.dg/asan/default-options-1.C: Likewise.

From-SVN: r229112