inline-asm/9981: attempt to read 64 bit pentium timestamp failure

[jon@mast.queensu.ca]

>Number:         9981
>Category:       inline-asm
>Synopsis:       attempt to read 64 bit pentium timestamp failure
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Mar 06 15:36:00 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     jon@mast.queensu.ca
>Release:        gcc 3.2
>Organization:
>Environment:

>Description:
Inline assembly to read 64 bit pentium timer fails with

testrdtsc.c:7: can't find a register in class `AD_REGS' while reloading `asm'

under gcc 3.2 . The info seems to indicate =A constraint allows a 64 bit result.
>How-To-Repeat:
gcc -g -O6 -o testrdtsc testrdtsc.c
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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