Modularize bignums better

* src/bignum.c, src/bignum.h: New files.  Only modules that
need to know how bignums are implemented should include
bignum.h.  Currently these are alloc.c, bignum.c (of course),
data.c, emacs.c, emacs-module.c, floatfns.c, fns.c, print.c.
* src/Makefile.in (base_obj): Add bignum.o.
* src/alloc.c (make_bignum_str): Move to bignum.c.
(make_number): Remove; replaced by bignum.c’s make_integer.
All callers changed.
* src/conf_post.h (ARG_NONNULL): New macro.
* src/json.c (json_to_lisp): Use it.
* src/data.c (Fnatnump):
Move NATNUMP’s implementation here from lisp.h.
* src/data.c (Fnumber_to_string):
* src/editfns.c (styled_format):
Move conversion of string to bignum to bignum_to_string, and
call it here.
* src/emacs-module.c (module_make_integer):
* src/floatfns.c (Fabs):
Simplify by using make_int.
* src/emacs.c: Include bignum.h, to expand its inline fns.
* src/floatfns.c (Ffloat): Simplify by using XFLOATINT.
(rounding_driver): Simplify by using double_to_bignum.
(rounddiv_q): Clarify use of temporaries.
* src/lisp.h: Move decls that need to know bignum internals to
bignum.h.  Do not include gmp.h or mini-gmp.h; that is now
bignum.h’s job.
(GMP_NUM_BITS, struct Lisp_Bignum, XBIGNUM, mpz_set_intmax):
Move to bignum.h.
(make_int): New function.
(NATNUMP): Remove; all callers changed to use Fnatnump.
(XFLOATINT): If arg is a bignum, use bignum_to_double, so that
bignum internals are not exposed here.
* src/print.c (print_vectorlike): Use SAFE_ALLOCA to avoid the
need for a record_unwind_protect_ptr.

1 files changed, 6 insertions, 3 deletions

diff --git a/src/print.c b/src/print.c
index 824f8d75779..49d9e38e7d3 100644
--- a/src/print.c
+++ b/src/print.c
@@ -23,6 +23,7 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 #include "sysstdio.h"
 
 #include "lisp.h"
+#include "bignum.h"
 #include "character.h"
 #include "coding.h"
 #include "buffer.h"
@@ -1369,10 +1370,12 @@ print_vectorlike (Lisp_Object obj, Lisp_Object printcharfun, bool escapeflag,
     {
     case PVEC_BIGNUM:
       {
-	struct Lisp_Bignum *b = XBIGNUM (obj);
-	char *str = mpz_get_str (NULL, 10, b->value);
-	record_unwind_protect_ptr (xfree, str);
+	USE_SAFE_ALLOCA;
+	char *str = SAFE_ALLOCA (mpz_sizeinbase (XBIGNUM (obj)->value, 10)
+				 + 2);
+	mpz_get_str (str, 10, XBIGNUM (obj)->value);
 	print_c_string (str, printcharfun);
+	SAFE_FREE ();
       }
       break;