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From: Hui Zhu <teawater@gmail.com>
Date: Sun, 18 Oct 2009 01:53:00 -0000
Message-ID: <daef60380910171852t3261114fscb6ee9d4d82fd005@mail.gmail.com>
Subject: Re: [RFA] record.c - save some memory in record log.
To: Joel Brobecker <brobecker@adacore.com>
Cc: Michael Snyder <msnyder@vmware.com>,  	"gdb-patches@sourceware.org" <gdb-patches@sourceware.org>
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>
> One way that we have used in the past that might be helpful here
> is to define the buffer at the end of the structure and without
> the pointer indirection:
>
> =A0 struct blah
> =A0 {
> =A0 =A0 ...
>
> =A0 =A0 int buffer_len;
> =A0 =A0 gdb_byte buf[0];
> =A0 };
>
> The allocation of the structure become a little trickier. And access
> to the buffer is a little more dangerous, which is why I don't like
> this approach much. =A0But it does save memory, and you can prevent
> buffer overrun by forcing access to this data through accessor
> routines...
>

Hi Joel,

But I think:
+  union
+  {
+    gdb_byte *ptr;
+    gdb_byte buf[2 * sizeof (gdb_byte *)];

Make the size of buf more clear.

Thanks,
Hui