Re: (Hardware?) problem with denormal values on mipsel

Ole Streicher <[email protected]>
Newsgroups gmane.linux.debian.ports.mips,gmane.linux.debian.devel.kernel
Message-ID <[email protected]>
Hi all,

Am 27.05.2015 um 15:45 schrieb James Cowgill:
> There's probably still a hardware bug in here somewhere, but before 3.16
> the kernel was fixing it with the math emulator.

Without understanding the discussion in detail, I'd like to bring a few
points here back: the issue is not about SIGILL on *any* call of sqrt; it is
just when it is called with a denormal number. Using f.e. 1.134e-32 f.e.
worked for me.

Also, the minimal "C" analogon

#include <math.h>
int main(void) {
  float r = 1.1342362e-39;
  r = sqrt(r);
  exit(0);
}

works without problem.
It is something specific what gfortran produces (and not gcc), and it is not
just a missing emulation (since normalized numbers work); it may be an
incomplete emulation.

Best regards

Ole
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