Greetings.
Are statically allocated two-dimensional arrays guaranteed to be
contiguous, or is it possible the compiler will allocate padding after
each row? Is the following code OK?
#include <string.h>
int main(void) {
char a[5][5];
memset(a, 'x', 25);
return 0;
}
Regards,
Tristan
--
_
_V.-o Tristan Miller [en,(fr,de,ia)] >< Space is limited
/ |`-' -=-=-=-=-=-=-=-=-=-=-=-=-=-=-= < In a haiku, so it's hard
(7_\\ http://www.nothingisreal.com/ >< To finish what you 3 5427
On Aug 15, 1:38*pm, Tristan Miller <psychon...@nothingisreal.com>
wrote:
Greetings.
Are statically allocated two-dimensional arrays guaranteed to be
contiguous, or is it possible the compiler will allocate padding after
each row? *Is the following code OK?
#include <string.h>
int main(void) {
* char a[5][5];
* memset(a, 'x', 25);
* return 0;
}
Regards,
Tristan
--
* *_
* _V.-o *Tristan Miller [en,(fr,de,ia)] *>< *Space is limited
*/ |`-' *-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*<*In a haiku, so it's hard
(7_\\ * *http://www.nothingisreal.com/* >< *To finish what you
As far as I know they are.
Tristan Miller wrote:
Greetings.
Are statically allocated two-dimensional arrays guaranteed to be
contiguous,
Yes.
or is it possible the compiler will allocate padding after
each row?
No.
Is the following code OK?
Yes.
#include <string.h>
int main(void) {
char a[5][5];
memset(a, 'x', 25);
return 0;
}
--
pete
Tristan Miller <ps********@nothingisreal.comwrites:
Are statically allocated two-dimensional arrays guaranteed to be
contiguous, or is it possible the compiler will allocate padding after
each row? Is the following code OK?
#include <string.h>
int main(void) {
char a[5][5];
memset(a, 'x', 25);
return 0;
}
Yes, because you're treating the object as an array of characters.
On the other hand, this:
a[0][5] = 'y';
will probably set a[1][0] to 'y', but it's not guaranteed; strictly
speaking, it's undefined behavior.
--
Keith Thompson (The_Other_Keith) ks***@mib.org <http://www.ghoti.net/~kst>
Nokia
"We must do something. This is something. Therefore, we must do this."
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