2 files changed, 9 insertions, 7 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index e2b1b294968..c747a325139 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -2,6 +2,9 @@
 
         * alloc.c (Fmake_bool_vector): Don't assume vector size fits in int.
         (allocate_vectorlike): Check for ptrdiff_t overflow.
+        (mark_vectorlike, mark_char_table, mark_object): Avoid EMACS_UINT
+        when a (possibly-narrower) signed value would do just as well.
+        We prefer using signed arithmetic, to avoid comparison confusion.
 
         * alloc.c: Catch some string size overflows that we were missing.
         (XMALLOC_OVERRUN_CHECK_SIZE) [!XMALLOC_OVERRUN_CHECK]: Define to 0,
diff --git a/src/alloc.c b/src/alloc.c
index 2dbaef9b00b..1307ad60234 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -5265,8 +5265,8 @@ static size_t mark_object_loop_halt;
 static void
 mark_vectorlike (struct Lisp_Vector *ptr)
 {
-  register EMACS_UINT size = ptr->header.size;
-  register EMACS_UINT i;
+  EMACS_INT size = ptr->header.size;
+  EMACS_INT i;
 
   eassert (!VECTOR_MARKED_P (ptr));
   VECTOR_MARK (ptr);            /* Else mark it */
@@ -5288,8 +5288,8 @@ mark_vectorlike (struct Lisp_Vector *ptr)
 static void
 mark_char_table (struct Lisp_Vector *ptr)
 {
-  register EMACS_UINT size = ptr->header.size & PSEUDOVECTOR_SIZE_MASK;
-  register EMACS_UINT i;
+  int size = ptr->header.size & PSEUDOVECTOR_SIZE_MASK;
+  int i;
 
   eassert (!VECTOR_MARKED_P (ptr));
   VECTOR_MARK (ptr);
@@ -5417,12 +5417,11 @@ mark_object (Lisp_Object arg)
            recursion there.  */
         {
           register struct Lisp_Vector *ptr = XVECTOR (obj);
-          register EMACS_UINT size = ptr->header.size;
-          register EMACS_UINT i;
+          int size = ptr->header.size & PSEUDOVECTOR_SIZE_MASK;
+          int i;
 
           CHECK_LIVE (live_vector_p);
           VECTOR_MARK (ptr);    /* Else mark it */
-          size &= PSEUDOVECTOR_SIZE_MASK;
           for (i = 0; i < size; i++) /* and then mark its elements */
             {
               if (i != COMPILED_CONSTANTS)