Avoid and simplify rb_alloc_tmp_buffer_with_count

There's no reason to ever call this and the "count" value is ignored.
Because this is part of the public API I left it as a stub, but it could
likely be removed.

Author: jhawthorn

imemo.c

@@ -63,29 +63,27 @@ rb_imemo_tmpbuf_new(void)
 }
 
 void *
-rb_alloc_tmp_buffer_with_count(volatile VALUE *store, size_t size, size_t cnt)
+rb_alloc_tmp_buffer(volatile VALUE *store, long len)
 {
+    if (len < 0) {
+        rb_raise(rb_eArgError, "negative buffer size (or size too big)");
+    }
+
     /* Keep the order; allocate an empty imemo first then xmalloc, to
      * get rid of potential memory leak */
     rb_imemo_tmpbuf_t *tmpbuf = (rb_imemo_tmpbuf_t *)rb_imemo_tmpbuf_new();
     *store = (VALUE)tmpbuf;
-    void *ptr = ruby_xmalloc(size);
+    void *ptr = ruby_xmalloc(len);
     tmpbuf->ptr = ptr;
-    tmpbuf->size = size;
+    tmpbuf->size = len;
 
     return ptr;
 }
 
 void *
-rb_alloc_tmp_buffer(volatile VALUE *store, long len)
+rb_alloc_tmp_buffer_with_count(volatile VALUE *store, size_t size, size_t cnt)
 {
-    long cnt;
-
-    if (len < 0 || (cnt = (long)roomof(len, sizeof(VALUE))) < 0) {
-        rb_raise(rb_eArgError, "negative buffer size (or size too big)");
-    }
-
-    return rb_alloc_tmp_buffer_with_count(store, len, cnt);
+    return rb_alloc_tmp_buffer(store, (long)size);
 }
 
 void

include/ruby/internal/memory.h

@@ -741,8 +741,7 @@ static inline void *
 rb_alloc_tmp_buffer2(volatile VALUE *store, long count, size_t elsize)
 {
     const size_t total_size = rbimpl_size_mul_or_raise(RBIMPL_CAST((size_t)count), elsize);
-    const size_t cnt = (total_size + sizeof(VALUE) - 1) / sizeof(VALUE);
-    return rb_alloc_tmp_buffer_with_count(store, total_size, cnt);
+    return rb_alloc_tmp_buffer(store, (long)total_size);
 }
 
 RBIMPL_SYMBOL_EXPORT_BEGIN()