[Bug c/16721] [3.5 Regression] Accesses to volatile objects optimized away

[falk at debian dot org]

------- Additional Comments From falk at debian dot org  2004-07-26 19:04 -------
I can reproduce this on alphaev68-linux.

In the test case you gave, removing the access seems entirely appropriate
to me, since addr is not volatile.

However, the same happens if you mark it volatile, so this is really a bug.
-fno-strict-aliasing is a red herring; the access also gets optimized away for

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

at -O2.


-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
           Severity|normal                      |critical
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|                            |1
           Keywords|                            |wrong-code
      Known to fail|                            |3.5.0
      Known to work|                            |3.3.4
            Summary|Accesses to volatile objects|[3.5 Regression] Accesses to
                   |optimized away with -fno-   |volatile objects optimized
                   |strict-aliasing             |away
   Target Milestone|---                         |3.5.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16721