0.7 / 1.0 ?= 0.52

Torbjorn Granlund tg at gmplib.org
Fri Jun 15 17:18:38 CEST 2012


Hans Aberg <haberg-1 at telia.com> writes:

  I had to wrap it into a function, and change the Haskell style '--'
  comments into C/C++ style (see below). Then just use any of the
  compilers mentioned above.
  

    gmp_printf ("%.*Ff \n", 5, b);	// Prints 1.00000
    
    mpf_div(l, a, b);
    gmp_printf ("%.*Ff", 5, l);		// Prints 0.70000
  
Wait a minute, you edited the comment to say what your expect to get
printed!  Perhaps the pesky llvm read your comment and got things right
as a result?

(Seriously though, we cannot draw any conclusion by this debacle.  The
guy might have really buggy code which corrupted the heap and stack,
provoking a state in which anything can happen from a GMP call.  I think
that's actually at least as likely as having struck an llvm bug.  No
real test case, no case!)

-- 
Torbjörn


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