Is a comma in an array initializer a sequence point?

Asked Apr 06 '16 at 21:29

Active Apr 07 '16 at 07:08

Viewed 121 times

I am not sure if a comma in an array initializer is actually a sequence point. Has the statement below defined behavior? The standard does not discuss side-effects during aggregate initialization specifically (I think), so I assumed implementation behavior myself, but I had to ask

char s[7] = {'a', s[0], s[1], s[2], s[3], s[4], 0};

 int a[3]= { *ptr++,*ptr++,*ptr++}

edited Apr 07 '16 at 07:08

2501

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asked Apr 06 '16 at 21:29

Bharat Ahuja

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Whether it is or not, I hope never to see this code in a real-world application. – owacoder Apr 06 '16 at 21:32
but we can see the second one – Bharat Ahuja Apr 06 '16 at 21:34
The first one does not compile in gcc. – Robert Jacobs Apr 06 '16 at 21:35
Yes, initializer lists are guaranteed left to right. – Nir Friedman Apr 06 '16 at 21:38
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@owacoder anyone who works for me and writes code like that, doesn't work for me :) – Martin James Apr 06 '16 at 22:36
An initialiser list has to contain _constant expressions_ only in C. Not sure about C++, this is a different language. – too honest for this site Apr 06 '16 at 23:07
I'm courious if the Answer there applys to C language too. It seems to be a C++ one. – Michi Apr 07 '16 at 02:49
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Unlike in C++, behavior is undefined in C. – 2501 Apr 07 '16 at 07:09

Is a comma in an array initializer a sequence point?

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