gmp-6.1.99-20171027/mpz/mul_i.h:105]: (style) Checking if unsigned variable 'small_mult' is less than zero.

[Torbjörn Granlund]

  >What do you think is buggy about the code?
    
  In the cases where small_mult is unsigned, it is pointless to test small_mult < 0.
  
It is not always unsigned.

A useful exercise might be to make the change you have in mind, rebuild
GMP and run make check.

-- 
Torbjörn
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