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From: diamond@csl.sony.co.jp (Norman Diamond)
Newsgroups: comp.std.c
Subject: sizeof on a word-oriented machine
Message-ID: <11135@riks.csl.sony.co.jp>
Date: 16 Nov 89 08:14:34 GMT
Reply-To: diamond@ws.sony.junet (Norman Diamond)
Organization: Sony Computer Science Laboratory Inc., Tokyo, Japan
Lines: 25

Consider a machine where each 4-byte word has an address.

  char x[37];
  int  q;
  q = sizeof x / sizeof (char);

What is sizeof x?

If sizeof x is 40 (since 40 bytes are reserved for x) then the example
on page 46 lines 12 to 13 (section 3.3.3.4) is violated.

If sizeof x is 37 then a user might do:
  char *two_xs;
  two_xs = malloc (2 * sizeof x);
and get screwed because only 76 bytes will be allocated (2 * 37 rounded
up to a multiple of 4) when 80 are really needed.

I think 40 is the most reasonable value for sizeof x.  Is the standard's
example wrong?  May it be ignored?

-- 
Norman Diamond, Sony Corp. (diamond%ws.sony.junet@uunet.uu.net seems to work)
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