From 8e53493c06cd798476a79238523d566582a0430a Mon Sep 17 00:00:00 2001
From: Pip Cet <pipcet@protonmail.com>
Date: Tue, 23 Jul 2024 18:57:34 +0000
Subject: [PATCH] dump bignums properly

---
 lisp/loadup.el | 2 ++
 src/alloc.c    | 2 +-
 src/bignum.c   | 3 +++
 src/igc.c      | 6 ++----
 src/pdumper.c  | 6 ++++--
 5 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/lisp/loadup.el b/lisp/loadup.el
index 6d1e13f44bf..df178b3bb2f 100644
--- a/lisp/loadup.el
+++ b/lisp/loadup.el
@@ -184,6 +184,8 @@
   (file-error
    (load "ldefs-boot.el")))
 
+(setq foo (lsh 1 92))
+
 (let ((new (make-hash-table :test #'equal)))
   ;; Now that loaddefs has populated definition-prefixes, purify its contents.
   (maphash (lambda (k v) (puthash (purecopy k) (purecopy v) new))
diff --git a/src/alloc.c b/src/alloc.c
index 320a5adaf0b..3c10a1b605f 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -6118,7 +6118,7 @@ make_pure_float (double num)
 /* Value is a bignum object with value VALUE allocated from pure
    space.  */
 
-static Lisp_Object
+Lisp_Object
 make_pure_bignum (Lisp_Object value)
 {
   mpz_t const *n = xbignum_val (value);
diff --git a/src/bignum.c b/src/bignum.c
index 1fe195d78ea..57e92599cc6 100644
--- a/src/bignum.c
+++ b/src/bignum.c
@@ -48,6 +48,9 @@ xfree_for_gmp (void *ptr, size_t ignore)
   xfree (ptr);
 }
 
+extern Lisp_Object
+make_pure_bignum (Lisp_Object value);
+
 void
 init_bignum (void)
 {
diff --git a/src/igc.c b/src/igc.c
index ad5f7cc3e7a..d1cdce82f98 100644
--- a/src/igc.c
+++ b/src/igc.c
@@ -4766,8 +4766,7 @@ igc_dump_finish_obj (void *client, enum igc_obj_type type,
 	igc_assert (base + obj_size (h) >= end);
 	if (type != IGC_OBJ_DUMPED_BYTES &&
 	    type != IGC_OBJ_DUMPED_CODE_SPACE_MASKS &&
-	    type != IGC_OBJ_DUMPED_BUFFER_TEXT &&
-	    type != IGC_OBJ_DUMPED_BIGNUM_DATA)
+	    type != IGC_OBJ_DUMPED_BUFFER_TEXT)
 	  *out = *h;
 	igc_assert (header_nwords (out) > 0);
 	return base + obj_size (h);
@@ -4780,8 +4779,7 @@ igc_dump_finish_obj (void *client, enum igc_obj_type type,
   type = (is_pure (client)
 	  ? pure_obj_type_and_hash (&hash, type, client)
 	  : builtin_obj_type_and_hash (&hash, type, client));
-  if (type != IGC_OBJ_DUMPED_BIGNUM_DATA)
-    set_header (out, type, nbytes, hash);
+  set_header (out, type, nbytes, hash);
   return base + nbytes;
 }
 
diff --git a/src/pdumper.c b/src/pdumper.c
index 996bdc79106..0f82be46e75 100644
--- a/src/pdumper.c
+++ b/src/pdumper.c
@@ -913,7 +913,8 @@ dump_igc_start_obj (struct dump_context *ctx, enum igc_obj_type type,
   ctx->igc_base_offset = ctx->offset;
   if (ctx->flags.dump_object_contents &&
       (type == IGC_OBJ_DUMPED_BYTES ||
-       type == IGC_OBJ_DUMPED_CODE_SPACE_MASKS))
+       type == IGC_OBJ_DUMPED_CODE_SPACE_MASKS ||
+       type == IGC_OBJ_DUMPED_BIGNUM_DATA))
     {
       /* This saving of obj_offset is Because of an assertion in
 	 dump_write. */
@@ -3638,8 +3639,9 @@ dump_cold_bignum (struct dump_context *ctx, Lisp_Object object)
   eassert (sz_nlimbs < DUMP_OFF_MAX);
   dump_align_output (ctx, alignof (mp_limb_t));
   dump_off nlimbs = (dump_off) sz_nlimbs;
+  char *dummy = (void *)igc_alloc_bytes (nlimbs * sizeof (mp_limb_t));
 # ifdef HAVE_MPS
-  dump_igc_start_obj (ctx, IGC_OBJ_DUMPED_BIGNUM_DATA, n);
+  dump_igc_start_obj (ctx, IGC_OBJ_DUMPED_BIGNUM_DATA, dummy - sizeof (uint64_t));
 # endif
   Lisp_Object descriptor
     = list2 (dump_off_to_lisp (ctx->offset),
-- 
2.45.2