expected out put is not coming

[Bhavith]

#include <stdio.h>
int a =1
int a;
int main()
{

	printf("%d\n",a); // expected 0 but o/p is 1 why ? 
	return 0;
}

1

[Chervil]

There's an error at line 2, the code does not compile because of a missing semicolon.
Also there's an error, int a is defined twice, on lines 2 and 3.

[kbw]

... along with a missing ; on line 2.

[Bhavith]

Sorry guys semicolon is there , It compiles fine and give ouput also

#include <stdio.h>
int a =1;
int a;
int main()
{

	printf("%d\n",a); // expected 0 but o/p is 1 why ? 
	return 0;
}

Please let me know why so wrong output

[Chervil]

I can't get this to compile as C++. I get an error

[Error]Multiple declaration for 'a'

or

[Error] redefinition of 'int a'

However, when compiled as C instead. it does seem to compile.
I'm not sure of the rules here, and how the two languages differ. I could guess (but that isn't useful).

[Chervil]

I found this article, which seems relevant:
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.faqs/ka16744.html

The important concept seems to be that of the tentative definition. A search for that term will bring up more information.

[Cubbi]

tentative definitions are also covered on cppreference here: http://en.cppreference.com/w/c/language/extern