Re: [Ltib] [SOLVED] Cross-compilation errors preventing build

[Stuart Hughes]

Hi Lionel,

No I don't think it's the same.

--disable-static just tell a build not to create the .a (static libraries) that may be part of the build.  The would be needed by something else wanting to statically link with that package's library.

The .la files are use to allow you to test shared libraries before you install them, they let you link to a non-install set of libraries.  This is fine for self-hosted development, but will not work when you are cross compiling.  In fact it's worse than that, it will make the cross compilation pick up host libraries (which will be the wrong architecture).

To try to clarify, if you installed the .la files on the target image, they could be used if you natively compiled on a board running that target image.  However due to the way LTIB works, it stages the target image in rootfs and libraries under rootfs/usr/lib are used during cross compilation.  That is why you need to remove these as any .la files under rootfs will poison your cross compilation.

Regards, Stuart

On 25/01/15 19:22, Leonard Pimentel wrote:

Stuart,

 

I apologize for the delay.  Thank you for the clarification.   Is the option flag “—disable-static” effectively the same as removing the *.la and *.a files using the “rm –f $RPM_BUILD_ROOT/mypackage/*.la” command?

 

Regards,

 

Leo

 

From: Stuart Hughes [mailto:address@hidden]
Sent: Sunday, January 18, 2015 1:23 PM
To: Leonard Pimentel
Cc: address@hidden
Subject: Re: [SOLVED] Cross-compilation errors preventing build

 

Hi Leonard,

 

I’m not sure I completely follow, however it is essential that all the .la files are removed from the binary rpm file.

 

The reason is that the binary gets installed in the local project area on the host under rootfs/… any .la files under there will get picked up by later packages when cross compiling and will cause the compiler to try to link to libraries under /usr/lib /lib on the host, which is clearly not what you want.

 

Regards, Stuart

 

On 15 Jan 2015, at 18:22, Leonard Pimentel <address@hidden> wrote:

Stuart Hughes,

 

Thank you.  Several times the cross-compilation would interrupt with errors and I could not understand why the *.la file was important to the compilation.

 

It was unforeseen that an innocuous statement would create cross-compilation build and install problems.

 

find $RPM_BUILD_ROOT%{pfx}%{_prefix}/lib/ -name “*.la” | xargs rm -f

 

After removing the above statement, warnings such “file moved” and the error “no such file or directory found” were commonplace.

 

http://lists.gnu.org/archive/html/ltib/2010-04/msg00127.html

 

 

 

From: Leonard Pimentel 
Sent: Wednesday, January 14, 2015 11:08 AM
To: 'address@hidden'
Subject: Cross-compilation errors preventing build

 

General cross-compiling question

 

Are there two solutions (at minimum) to solve the following warning [file moved] and error [no such file]?  I am running into build errors.  Help is appreciated.

 

Error log snippet:

 

libtool: link: warning: library `/home/leo/logic/Logic_BSPs/Linux_3.0/1026167_LogicPD_Linux_BSP_2.4-3/rootfs/usr/lib/libgstvideo-0.10.la' was moved.

/bin/sed: can't read /usr/lib/libgstinterfaces-0.10.la: No such file or directory

libtool: link: `/usr/lib/libgstinterfaces-0.10.la' is not a valid libtool archive

make[3]: *** [libgstaudiofx.la] Error 1

make[3]: Leaving directory `/home/leo/logic/Logic_BSPs/Linux_3.0/1026167_LogicPD_Linux_BSP_2.4-3/rpm/BUILD/gst-plugins-good-0.10.25/gst/audiofx'

make[2]: *** [audiofx] Error 2

make[3]: Leaving directory `/home/leo/logic/Logic_BSPs/Linux_3.0/1026167_LogicPD_Linux_BSP_2.4-3/rpm/BUILD/gst-plugins-good-0.10.25/gst/debugutils'

make[2]: Leaving directory `/home/leo/logic/Logic_BSPs/Linux_3.0/1026167_LogicPD_Linux_BSP_2.4-3/rpm/BUILD/gst-plugins-good-0.10.25/gst'

make[1]: *** [all-recursive] Error 1

 

 

 

Snippets from spec file

 

%define pfx          /opt/freescale/rootfs/%{_target_cpu}

%define LOGICPD_DIR  /home/leo/logic/Logic_BSPs/Linux_3.0/1026167_LogicPD_Linux_BSP_2.4-3

 

%Build

export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:%LOGICPD_FS/usr/lib/pkconfig

 

lt_cv_path_NM=nm \

./configure --prefix=%{_prefix} --host=$CFGHOST --build=%{_build} \

                --with-pkg-config-path=$PKG_CONFIG_PATH \

                CPPFLAGS=-I%LOGICPD_DIR/rootfs/usr/include/gstreamer-0.10/gst \

                LDFLAGS=-L%LOGICPD_DIR/rootfs/usr/lib \

 

%install

rm –rf $RPM_BUILD_ROOT

make install DESTDIR=${RPM_BUILD_ROOT}%{pfx}

 

 

 

The following comment from StackOverflow suggests setting the dependency_libs section. 

 

Have you looked inside the libfreetype.la file? Libtool .la files are just text files describing libraries. By default, they are commented. Search for the libdir and dependency_libs settings and check if they point to the right places.

 

How can this be accomplished either in the configuration statement or via a libtool –finish command?

 

Contents of two .la files.  Note the libdir is referenced the file system directory path under the cross-compilied target.

 

# libgstinterfaces-0.10.la - a libtool library file

# Generated by ltmain.sh (GNU libtool) 2.2.6b Debian-2.2.6b-2

#

# Please DO NOT delete this file!

# It is necessary for linking the library.

 

# The name that we can dlopen(3).

dlname='libgstinterfaces-0.10.so.0'

 

# Names of this library.

library_names='libgstinterfaces-0.10.so.0.21.0 libgstinterfaces-0.10.so.0 libgstinterfaces-0.10.so'

 

# The name of the static archive.

old_library='libgstinterfaces-0.10.a'

 

# Linker flags that can not go in dependency_libs.

inherited_linker_flags=' -pthread'

 

# Libraries that this one depends upon.

dependency_libs=' -L/home/leo/logic/Logic_BSPs/Linux_3.0/1026167_LogicPD_Linux_BSP_2.4-3/rootfs/usr/lib -lgstreamer-0.10 -lgobject-2.0 -lgmodule-2.0 -lgthread-2.0 -lrt -lxml2 -lglib-2.0 -lm'

 

# Names of additional weak libraries provided by this library

weak_library_names=''

 

# Version information for libgstinterfaces-0.10.

current=21

age=21

revision=0

 

# Is this an already installed library?

installed=yes

 

# Should we warn about portability when linking against -modules?

shouldnotlink=no

 

# Files to dlopen/dlpreopen

dlopen=''

dlpreopen=''

 

# Directory that this library needs to be installed in:

libdir='/usr/lib'

 

 

 

 

libgstaudio-0.10.la - a libtool library file

# Generated by ltmain.sh (GNU libtool) 2.2.6b Debian-2.2.6b-2

#

# Please DO NOT delete this file!

# It is necessary for linking the library.

 

# The name that we can dlopen(3).

dlname='libgstaudio-0.10.so.0'

 

# Names of this library.

library_names='libgstaudio-0.10.so.0.21.0 libgstaudio-0.10.so.0 libgstaudio-0.10.so'

 

# The name of the static archive.

old_library='libgstaudio-0.10.a'

 

# Linker flags that can not go in dependency_libs.

inherited_linker_flags=' -pthread'

 

# Libraries that this one depends upon.

dependency_libs=' -L/home/leo/logic/Logic_BSPs/Linux_3.0/1026167_LogicPD_Linux_BSP_2.4-3/rootfs/usr/lib -lgstbase-0.10 /usr/lib/libgstinterfaces-0.10.la -lgstreamer-0.10 -lgobject-2.0 -lgmodule-2.0 -lgthread-2.0 -lrt -lxml2 -lglib-2.0 -lm'

 

# Names of additional weak libraries provided by this library

weak_library_names=''

 

# Version information for libgstaudio-0.10.

current=21

age=21

revision=0

 

# Is this an already installed library?

installed=yes

 

# Should we warn about portability when linking against -modules?

shouldnotlink=no

 

# Files to dlopen/dlpreopen

dlopen=''

dlpreopen=''

 

# Directory that this library needs to be installed in:

libdir='/usr/lib'

 

 

 

Leonard Pimentel

CEO & CTO

Lotus Research, LLC.

Cell: (917) 834-7533

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