number_field_* leaks caused by gen.pyx's type(gen self)

[sagetrac-mabshoff]

We leak medium to massive amount of memory in a lot of number field related code. This is caused by

     def type(gen self):
        return str(type_name(typ(self.g)))

in gen.pyx. The regular and obvious fix causes segfualts in other places (i.e. due to integer.pyx), so I am attaching a workaround fix that has some performance penalty.

Cheers,

Michael

Component: memleak

Issue created by migration from https://trac.sagemath.org/ticket/4117

[sagetrac-mabshoff]

Attachment: trac_4117.patch.gz

This is a diff with some work around code

[craigcitro]

Different fix for the same problem

[sagetrac-mabshoff]

comment:2

Attachment: trac-4117.patch.gz

Merged trac-4117.patch in Sage 3.1.2.rc3

[jdemeyer]

comment:3

I wonder why this was a memleak. The original code looks correct, so either there was a bug in PARI/GP, a bug in Cython or a mis-identified memleak.

After 9 years, I am reverting this is in sagemath/cypari2@8f8ec55