question about scope & linkage

[Karl Heuer]

In article <1002 at virtech.UUCP> cpcahil at virtech.UUCP (Conor P. Cahill) writes:
>A tentative definition of a data object is not resolved at the end of source
>module,  but at link time.  I quote from K&R2 pg 227 ...

As Doug mentioned, this is a Common Extension, not guaranteed to work on all
conforming implementations.

>BTW, I don't see how any of this applies to a "forward reference to
>non-global identifiers".

Consider a source file that contains
	static int x;
	int f() { return x; }
	static int x = 3;
The third line is the real definition of x; the second line contains a forward
reference to it, which is enabled by the tentative definition on the first
line.  In pre-ANSI C, this was not legal because "static int x;" was a real
definition with implied initializer zero (at least in some linkage models).

Karl W. Z. Heuer (ima!haddock!karl or karl at haddock.isc.com), The Walking Lint