[Bug c++/12590] New: inline asm impossible constraint in `asm'

[giffordj at linkline dot com]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12590

           Summary: inline asm impossible constraint in `asm'
           Product: gcc
           Version: 3.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c++
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: giffordj at linkline dot com
                CC: gcc-bugs at gcc dot gnu dot org

Compiles fine with no -O, but gives impossible constraint in `asm' when 
compiled with -O2 or -O3.

Code

inline jlong atomic::compare_and_exchange_long(jlong exchange_value, jlong*
dest, jlong compare_value) {
  jlong old_value;
  __asm__ volatile (  "pushl %%ebx;mov 4+%1,%%ecx;mov
%1,%%ebx;lock;cmpxchg8b (%3);popl %%ebx"
                    : "=A" (old_value)
                    : "o" (exchange_value), "A" (compare_value), "r" (dest)
                    : "%ebx", "%ecx", "memory");
  return old_value;
}