* regex.h (RE_NO_NEWLINE_ANCHOR): New syntax flag.

* regex.h (RE_NO_NEWLINE_ANCHOR): New syntax flag.
(struct re_pattern_buffer): Remove newline_anchor.
* regex.c: Keep namespace clean for GNU libc by renaming <fun>
to __<fun> and using `weak_alias (__<fun>, <fun>)'.
(re_max_failures, fail_stack): Use size_t rather than unsigned.
(regex_compile): For ^ and $, choose between buffer and line (beg|end)
depending on the new RE_NO_NEWLINE_ANCHOR syntax flag.
(print_compiled_pattern, re_search_2, mutually_exclusive_p)
(re_match_2_internal, re_compile_pattern, re_comp, regcomp):
Get rid of references to newline_anchor.
(regcomp): Allocate and precompute a fastmap.