Get rid of re_set_syntax

Instead of using a global variable for storing regex syntax, pass it
to re_compile_pattern.  This is only enabled when compiling Emacs (i.e.
‘#ifdef emacs’).

* src/regex.h (re_set_syntax): Declare only #ifndef emacs.
(re_compile_pattern): Now takes syntax argument #ifdef emacs.

* src/regex.c (re_syntax_options): Define only #ifndef emacs.
(re_compile_pattern): Use the new syntax argument #ifdef emacs.

* src/search.c (compile_pattern_1): Don’t use re_set_syntax and
instead pass syntax to re_compile_pattern directly.

1 files changed, 4 insertions, 6 deletions

diff --git a/src/search.c b/src/search.c
index 7cb18a2059a..f0419522df2 100644
--- a/src/search.c
+++ b/src/search.c
@@ -113,8 +113,8 @@ static void
 compile_pattern_1 (struct regexp_cache *cp, Lisp_Object pattern,
                    Lisp_Object translate, bool posix)
 {
+  reg_syntax_t syntax;
   char *val;
-  reg_syntax_t old;
 
   cp->regexp = Qnil;
   cp->buf.translate = (! NILP (translate) ? translate : make_number (0));
@@ -131,16 +131,15 @@ compile_pattern_1 (struct regexp_cache *cp, Lisp_Object pattern,
      Using BLOCK_INPUT here means the debugger won't run if an error occurs.
      So let's turn it off.  */
   /*  BLOCK_INPUT;  */
-  old = re_set_syntax (RE_SYNTAX_EMACS
-                       | (posix ? 0 : RE_NO_POSIX_BACKTRACKING));
 
   if (STRINGP (Vsearch_spaces_regexp))
     re_set_whitespace_regexp (SSDATA (Vsearch_spaces_regexp));
   else
     re_set_whitespace_regexp (NULL);
 
-  val = (char *) re_compile_pattern (SSDATA (pattern),
-                                     SBYTES (pattern), &cp->buf);
+  syntax = RE_SYNTAX_EMACS | (posix ? 0 : RE_NO_POSIX_BACKTRACKING);
+  val = (char *) re_compile_pattern (SSDATA (pattern), SBYTES (pattern),
+                                     syntax, &cp->buf);
 
   /* If the compiled pattern hard codes some of the contents of the
      syntax-table, it can only be reused with *this* syntax table.  */
@@ -148,7 +147,6 @@ compile_pattern_1 (struct regexp_cache *cp, Lisp_Object pattern,
 
   re_set_whitespace_regexp (NULL);
 
-  re_set_syntax (old);
   /* unblock_input ();  */
   if (val)
     xsignal1 (Qinvalid_regexp, build_string (val));