[Pkg-octave-devel] Bug#871214: Bug#871214: octave-image FTBFS on i386: test hangs

[Adrian Bunk <bunk@debian.org>]

On Thu, Aug 10, 2017 at 09:31:32AM +0200, Rafael Laboissière wrote:
> 
> I would guess that the culprit is the following unit test in bwdist:
> 
> ## The quasi-euclidean method is apparently sensitive to a machine precision
> ## error that happens in x86 systems only. This test will cause an endless
> ## loop in case of a regression.
>...

That explains why the problem happens on i386 (where the 387 FPU
that internally uses 80-bit precision is used) but not on amd64
(where gcc defaults to using SSE instead of the 387).

If the problem is only in the test case,
it should be disabled on any-i386.

But if the difference is actually considered a bug,
then the following in debian/rules fixes the problem:

DEB_HOST_ARCH ?= $(shell dpkg-architecture -qDEB_HOST_ARCH)

ifneq (,$(filter $(DEB_HOST_ARCH), i386))
    export DEB_CXXFLAGS_MAINT_APPEND=-ffloat-store
endif


> Rafael

cu
Adrian

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