PR16867: Fix a long standing DCE bug

[Andrew Pinski]

On Aug 11, 2004, at 11:25 PM, Diego Novillo wrote:

> This patch fixes PR 16867 by teaching the middle-end the difference
> between global variables, variables that need to reside in memory and
> call-clobbered variables.

Seems like this would fix PR 16721 also but I don't know:

struct data { volatile unsigned long addr; } p;
void test() { p.addr; }

There should be still an access to p.addr in the asm.


-- Pinski