Strange MXCSR messages?

Matthew Dillon dillon at
Fri Dec 14 14:10:27 PST 2007

:Ah, so it was our threading lib that was producing the erroneous data?
:That would explain why it happened only for threaded programs (so far) :)
:  simon

    Yup.  libc_r was running fnsave (387 format save frame) into the FP
    save area of the signal context.  The kernel tried to restore it
    with fxrstr (SSE format save frame).

    Since the kernel now saves and restores the FP state from the signal
    context, libc no longer has to do it so ripping the code out of libc
    solves the problem.

					Matthew Dillon 
					<dillon at>

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