On Thu, 13 Dec 2007 21:11, [EMAIL PROTECTED] said:
> volatile char buf[SIZE];
> /* ... do stuff with buf ... */
> memset(buf, 0, sizeof(buf));
This has the little disadvantage that you need to check the attributes
of BUF first and that you can't immediately see what the memset is used
for. For a long time we use the macros below to document the intention
and to make sure that the compiler does not do any harm:
/* To avoid that a compiler optimizes certain memset calls away, these
macros may be used instead. */
#define wipememory2(_ptr,_set,_len) do { \
volatile char *_vptr=(volatile char *)(_ptr); \
size_t _vlen=(_len); \
while(_vlen) { *_vptr=(_set); _vptr++; _vlen--; } \
} while(0)
#define wipememory(_ptr,_len) wipememory2(_ptr,0,_len)
Shalom-Salam,
Werner
--
Die Gedanken sind frei. Auschnahme regelt ein Bundeschgesetz.
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