[Debian-med-packaging] Bug#746863: FTBFS src:insighttoolkit4

[Gert Wollny]

> Il Mercoledì 2 Luglio 2014 13:15, Gert Wollny <gw.fossdev at gmail.com> 
> The failing command seems to be 
> 
> /usr/bin/gccxml -fxml-start=_cable_
> -fxml=/«PKGBUILDDIR»/BUILD/Wrapping/Modules/ITKCommon/vcl_complex.xml
>
--gccxml-gcc-options /«PKGBUILDDIR»/BUILD/Wrapping/Modules/ITKCommon/gcc_xml.inc 
> -DCSWIG -DCABLE_CONFIGURATION -DITK_MANUAL_INSTANTIATION 
> /«PKGBUILDDIR»/BUILD/Wrapping/Modules/ITKCommon/vcl_complex.cxx
> /usr/bin/cmake -E
cmake_progress_report /«PKGBUILDDIR»/BUILD/CMakeFiles 
> 
> Seems like something is wrong with the generated
> Wrapping/Modules/ITKCommon/gcc_xml.inc
> 

> is anybody making any progress with this?
> I found that with DITK_WRAP_PYTHON:BOOL=OFF
> but this seems not so helpful, unless we want to remove the python support, right?
Indeed. 

> I'm really lost about any possibility to fix this bug.
I had another take on it, and it seems that it is not actually a
mis-configuration on the part of gccxml, but ITK seems to expects that
SSE is enabled when emmintrin.h is available. 

If emmintrin.h is available then it is included. In gccxml for
gcc-4.7/4.8  the replacement  emmintrin.h does 

#ifndef __SSE2__
# error "SSE2 instruction set not enabled"
#else
...
#endif 

but in gcc-4.9 some gcc pragmas are used that are probably not
understood by gccxml. 

Still, I do not understand how the compile went through with earlier
versions of gcc, considering that the default build flags completely
disable SSE on Debian-i386 (since it still supports i486 processors) and
the #error directive should have been hit. 

The relevant include file tests that sets ITK_HAVE_EMMINTRIN_H comes
from  Modules/Core/Common/CMake/CheckSupportForSSERounding.cmake and
it's set in BUILD/Modules/Core/Common/itkConfigure.h


> The package is quite big, and studying it requires too much effort for my time
> 
> I hope somebody else will find a solution for this bug,
Well, I've added Matt from Kitware to the CC, maybe he can shed some
light on what might be going on here.

Best 
Gert