Re: [Discuss-gnuradio] I can't get my gsl to link

[Vasil Velichkov]

Hi Alan,

On 06/09/2019 19.18, Alan Corey wrote:
> It might help if I had more idea what's supposed to happen. 

The first command is suppose to print the list of directories your linker will 
look into when searching libraries. On my Fedora 29 x86_64 system it prints.

$ ld --verbose | grep SEARCH_DIR | tr -s ' ;' \\012
SEARCH_DIR("=/usr/x86_64-redhat-linux/lib64")
SEARCH_DIR("=/usr/lib64")
SEARCH_DIR("=/usr/local/lib64")
SEARCH_DIR("=/lib64")
SEARCH_DIR("=/usr/x86_64-redhat-linux/lib")
SEARCH_DIR("=/usr/local/lib")
SEARCH_DIR("=/lib")
SEARCH_DIR("=/usr/lib")

The second command is suppose to print all the commands used by "make" to build 
the library together with all their parameters.

> Was I supposed to define SEARCH_DIR?
No

Or replace it? 

No

> Is that 1 line or 2? 

2 separate commands

> Just running
>  ld --verbose | grep SEARCH_DIR | tr -s ' ;' \\012
> ld: fatal error: no input files

What ld version do you use and how did you install it?

In case you are building with gcc run

$ gcc -Xlinker --verbose  2>/dev/null | grep SEARCH | sed 
's/SEARCH_DIR("=\?\([^"]\+\)"); */\1\n/g'  | grep -vE '^$'

> Trying as 1 line:
> ld --verbose | grep SEARCH_DIR | tr -s ' ;' \\012 make VERBOSE=1
> tr: extra operand ‘make’
> Try 'tr --help' for more information.
> ld: fatal error: no input files

The two commands needs to be executed separately. 

> 
> From the stackoverflow example, if I put "-Wl,--verbose" in my
> CMakeCache.txt as part of the string that gets passed to the C
> compiler would that do it? 

I don't know.

> If I could use a more normal -L and -l I'd
> be more comfortable but I'm working through the full cmake process.  I
> don't know how to extract what I need to try to link this manually.

    make VERBOSE=1

or

    cd build/gr-fec
    find . -name link*.txt
    cat ./lib/CMakeFiles/gnuradio-fec.dir/link.txt

> Yup, aarch64 on an Odroid N2:
> Linux odroid 4.9.177+ #1 SMP PREEMPT Sat May 18 09:49:10 CEST 2019
> aarch64 GNU/Linux
> 
> Debian from meveric's image, still Stretch so far.  Some dependencies
> I built from source, some are from the debs if they were new enough.

ATM I don't have access to any ARM based systems but in Debian Testing 
container the output of ld commands is

$ ld --version
GNU ld (GNU Binutils for Debian) 2.32.51.20190821

$ ld --verbose | grep SEARCH_DIR | tr -s ' ;' \\012
SEARCH_DIR("=/usr/local/lib/x86_64-linux-gnu")
SEARCH_DIR("=/lib/x86_64-linux-gnu")
SEARCH_DIR("=/usr/lib/x86_64-linux-gnu")
SEARCH_DIR("=/usr/lib/x86_64-linux-gnu64")
SEARCH_DIR("=/usr/local/lib64")
SEARCH_DIR("=/lib64")
SEARCH_DIR("=/usr/lib64")
SEARCH_DIR("=/usr/local/lib")
SEARCH_DIR("=/lib")
SEARCH_DIR("=/usr/lib")
SEARCH_DIR("=/usr/x86_64-linux-gnu/lib64")
SEARCH_DIR("=/usr/x86_64-linux-gnu/lib")

And the important part is that the output includes /usr/local/lib and 
/usr/local/lib/x86_64-linux-gnu

> I disabled GR-WAVELET, FEC and GR-DTV, got it to build.  Ran
> volk_profile, it picked up the neon correctly.  I don't have an RF
> source driver so far.  Using an RTL2832 dongle, trying to build
> Osmocom. 

See https://lists.gnu.org/archive/html/discuss-gnuradio/2019-09/msg00036.html

> There's a ton of obsolete documentation out there.

Please consider proposing documentation updates.

> Probably doesn't matter but my LD_LIBRARY_PATH is
> /usr/local/lib:/lib:/lib/aarch64-linux-gnu:/usr/lib:/usr/lib/aarch64-linux-gnu

In my experience on most Linux distributions LD_LIBRARY_PATH and ldconfig cache 
are not used when building programs/libraries but only when running programs.

Cheers,
Vasil