py36-numpy crash on Mojave (workaround on #56954)

[lfarv (Laurent Farvacque)]

The function "dgelsd" (among others) creates a memory allocation failure on Mojave:

python(61682,0x1192915c0) malloc: can't allocate region
*** mach_vm_map(size=18446744071689490432) failed (error code=3)
python(61682,0x1192915c0) malloc: *** set a breakpoint in malloc_error_break to debug
init_dgelsd failed init

[mf2k (Frank Schima)]

In the future, please use WikiFormatting and add the port maintainer(s) to Cc (port info --maintainers py27-numpy), if any.

[mf2k (Frank Schima)]

Which compiler are you building with - i.e what is the output of following?

port installed py27-numpy

[lfarv (Laurent Farvacque)]

compiler: standard Mojave installation, Xcode 10 installed

(test27) bijou:~ $ port installed py27-numpy
The following ports are currently installed:
  py27-numpy @1.15.2_0+gfortran (active)

[mf2k (Frank Schima)]

How is this different than the issue reported in #56954?

[lfarv (Laurent Farvacque)]

The behaviour changed with Mojave, and I wanted it to appear on the "Mojave" list for users experiencing a sudden crash after updating their system (as I did).

[lpsinger (Leo Singer)]

I stumbled across this because np.polyfit was giving nonsense answers:

$ python -c 'import numpy as np; print(np.polyfit(np.arange(10), np.arange(10), 1))'
Python(94611,0x1125ca5c0) malloc: can't allocate region
*** mach_vm_map(size=18446744072329076736) failed (error code=3)
Python(94611,0x1125ca5c0) malloc: *** set a breakpoint in malloc_error_break to debug
init_dgelsd failed init
-c:1: RankWarning: Polyfit may be poorly conditioned
[1.21925297e-313 7.38137387e-313]

[lpsinger (Leo Singer)]

Could we please change the default variants so that this workaround is applied? It's very dangerous for us scientists working on macOS and using MacPorts that in some cases py37-numpy gives incorrect answers.

[michaelld (Michael Dickens)]

Thinking this is the same as #56954, so closing this ticket too.