swig: add symlink to /usr/bin/swig2.0

the cmake detection script provided with cmake will first look for a
binary called swig2.0 then for a binary called swig

swig-host only installs a binary called swig and gets overridden by the
version installed by the host distro. This symlink prevents that from
happening
---
 package/swig/swig.mk | 6 ++++++
 1 file changed, 6 insertions(+)

Dear Jérémy Rosen,

On Fri, 19 Sep 2014 09:13:51 +0200, Jérémy Rosen wrote:
> the cmake detection script provided with cmake will first look for a
> binary called swig2.0 then for a binary called swig
> 
> swig-host only installs a binary called swig and gets overridden by the
> version installed by the host distro. This symlink prevents that from
> happening

I don't understand the explanation: if it looks for a binary called
swig, then where's the need to create a swig2.0 symbolic link? How a
binary in $(HOST_DIR)/usr/bin can get overridden by the version
installed by the host distro?

The SoB line is missing.

> diff --git a/package/swig/swig.mk b/package/swig/swig.mk
> index 5efc81c..233e97d 100644
> --- a/package/swig/swig.mk
> +++ b/package/swig/swig.mk
> @@ -15,4 +15,10 @@ HOST_SWIG_CONF_OPT = \
>  SWIG_LICENSE = GPLv3+ BSD-2c BSD-3c
>  SWIG_LICENSE_FILES = LICENSE LICENSE-GPL LICENSE-UNIVERSITIES
>  
> +define SWIG_INSTALL_SYMLINK

Should be HOST_SWITCH_INSTALL_SYMLINK.

I've marked your patch as "Changes requested" in patchwork.

Thanks!

Thomas

----- Mail original -----
> Dear Jérémy Rosen,
> 
> On Fri, 19 Sep 2014 09:13:51 +0200, Jérémy Rosen wrote:
> > the cmake detection script provided with cmake will first look for
> > a
> > binary called swig2.0 then for a binary called swig
> > 
> > swig-host only installs a binary called swig and gets overridden by
> > the
> > version installed by the host distro. This symlink prevents that
> > from
> > happening
> 
> I don't understand the explanation: if it looks for a binary called
> swig, then where's the need to create a swig2.0 symbolic link? How a
> binary in $(HOST_DIR)/usr/bin can get overridden by the version
> installed by the host distro?
> 

The line in FindSwig.mk (part of the cmake package, not swig package)

find_program(SWIG_EXECUTABLE NAMES swig2.0 swig)


This will look in PATH for

* an executable called "swig2.0"
* if it is not found, an executable called "swig"

so if there is a "swig2.0" in /usr/bin it will be used instead of the
one called "swig" in $(HOST_DIR)/usr/bin even if the PATH order says
otherwise.

currently, host-swig only installs $(HOST_DIR)/usr/bin/swig and the
debian package on my host only installs /usr/bin/swig2.0 thus the 
problem.


(Note that the separate bump of cmake changes the cmake line above to 
dealwith swig3.0 that has been updated since, but using 
$(MAJOR_VERSION) deals with it properly)


> The SoB line is missing.


OK

> 
> > diff --git a/package/swig/swig.mk b/package/swig/swig.mk
> > index 5efc81c..233e97d 100644
> > --- a/package/swig/swig.mk
> > +++ b/package/swig/swig.mk
> > @@ -15,4 +15,10 @@ HOST_SWIG_CONF_OPT = \
> >  SWIG_LICENSE = GPLv3+ BSD-2c BSD-3c
> >  SWIG_LICENSE_FILES = LICENSE LICENSE-GPL LICENSE-UNIVERSITIES
> >  
> > +define SWIG_INSTALL_SYMLINK
> 
> Should be HOST_SWITCH_INSTALL_SYMLINK.
> 

OK

> I've marked your patch as "Changes requested" in patchwork.
> 

Ok, thx, I'll fix all that, rebase and resubmit

Thx for the review

> Thanks!
> 
> Thomas
> --
> Thomas Petazzoni, CTO, Free Electrons
> Embedded Linux, Kernel and Android engineering
> http://free-electrons.com
>

Hello,

On Mon, 22 Sep 2014 09:38:29 +0200 (CEST), Jeremy Rosen wrote:

> The line in FindSwig.mk (part of the cmake package, not swig package)
> 
> find_program(SWIG_EXECUTABLE NAMES swig2.0 swig)
> 
> 
> This will look in PATH for
> 
> * an executable called "swig2.0"
> * if it is not found, an executable called "swig"
> 
> so if there is a "swig2.0" in /usr/bin it will be used instead of the
> one called "swig" in $(HOST_DIR)/usr/bin even if the PATH order says
> otherwise.
> 
> currently, host-swig only installs $(HOST_DIR)/usr/bin/swig and the
> debian package on my host only installs /usr/bin/swig2.0 thus the 
> problem.

Are you sure we cannot tell CMake explicitly where our swig binary is?
Like -DSWIG_EXECUTABLE=/path/to/swig.

Cc'ing Samuel, who should be able to give some hints about this.

Thanks,

Thomas