Why am I seeing the following warning: warning: ‘i’ initialized and declared ‘extern’
#include<stdio.h>
extern int i = 1;
int main()
{
return 0;
}
main.c:4:12: warning: ‘i’ initialized and declared ‘extern’ extern int i = 1;
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Zalhera
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Sunil Rathod
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1`extern` means that the variable is defined in another compilation unit that you're going to link with this. – Barmar Oct 18 '19 at 21:37
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Why are you using `extern` when that is not declared externally? – tadman Oct 18 '19 at 21:38
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2This is valid C (the `extern` is doing nothing), but rather pointless to write. It's definitely anti-idiomatic to write `extern` when you're providing a definition. – R.. GitHub STOP HELPING ICE Oct 18 '19 at 21:51
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2See C11 [§6.9.2 External object definitions ¶4](http://port70.net/~nsz/c/c11/n1570.html#6.9.2p4), which is a non-normative example that includes the line: `extern int i3 = 3; // definition, external linkage` — which strongly suggests that the standard thinks it is OK, even though GCC does not. – Jonathan Leffler Oct 18 '19 at 21:55
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1Time to post a GCC bug? – Antti Haapala -- Слава Україні Oct 19 '19 at 05:11