Taking the address of local variables

[Suspended in Gaffa]

In article <6472 at june.cs.washington.edu> pardo at cs.washington.edu (David Keppel) writes:

	[stuff about taking the address of a local variable]

I believe that the way this is COMMONLY dealt with is the following:

	When the compiler sees the address taken of a local variable,
	it is forced to treat this as basically "volatile" in a way.
	All modifications to that variable must be written out
	to memory AT THE EARLIER location.  This variable cannot
	be moved.

	Now, some optimizations are possible.
	-- If the address goes into a local variable only,
	the compiler can keep track of it's use, and verify
	correctness within this function.
	-- however, if the value gets stored into a global
	variable or passed to a function, then all bets
	are off.  Any following function call or global
	pointer reference (after a function call), could
	use that pointer value.

	So, the summary is :

		DON'T TAKE THE ADDRESSES OF VARIABLES
		IF YOU WANT YOUR COMPILER TO DO OPTIMIZATIONS!!!
	


--chris
The more things change, the more they stay insane.
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