Could not find LAPACK library

[Andrew Lambe]

I'm trying to include the bundled UMFPACK package in my deal.II installation, but when I switch the options DEAL_II_WITH_LAPACK and DEAL_II_WITH_UMFPACK on, I get a weird error from CMake that the LAPACK library is not detected. I say weird because I have installed BLAS and LAPACK in the default location /usr/lib (via Ubuntu packages). If I switch these options off, the configuration and compile run without issue. Specifying the directory via the LAPACK_DIR option doesn't help.

Unfortunately, I need UMFPACK to run some of my existing examples so I want those options to be on. I recently upgraded my Ubuntu version via a fresh install, so this could be the source of the issue, (missing package, broken link, etc.) but I'm having trouble chasing it down.

I have included the terminal output with the above options off (terminal_out_ok.txt) and on (terminal_out_bad.txt) as well as the error logs for the second case. Any help would be appreciated.

[Wolfgang Bangerth]

Andrew,
can you post the output of
ls -l /usr/lib/liblapack*
or of
ls -l /usr/lib64/liblapack*
depending on whether you have a 32 or 64 bit system?

Best
W.

--
------------------------------------------------------------------------
Wolfgang Bangerth email: bang...@colostate.edu
www: http://www.math.colostate.edu/~bangerth/

[Andrew Lambe]

Here it is:

andrew@andrew-apple-laptop:~/dealii-8.3.0/build$ ls -l /usr/lib/liblapack*
lrwxrwxrwx 1 root root 29 Sep 21 11:54 /usr/lib/liblapack.a -> /etc/alternatives/liblapack.a
lrwxrwxrwx 1 root root 28 Nov 23  2015 /usr/lib/liblapack_atlas.a -> atlas-base/liblapack_atlas.a
lrwxrwxrwx 1 root root 29 Nov 23  2015 /usr/lib/liblapack_atlas.so -> atlas-base/liblapack_atlas.so
lrwxrwxrwx 1 root root 31 Nov 23  2015 /usr/lib/liblapack_atlas.so.3 -> atlas-base/liblapack_atlas.so.3
lrwxrwxrwx 1 root root 30 Sep 21 11:54 /usr/lib/liblapack.so -> /etc/alternatives/liblapack.so
lrwxrwxrwx 1 root root 32 Sep 15 12:19 /usr/lib/liblapack.so.3 -> /etc/alternatives/liblapack.so.3
lrwxrwxrwx 1 root root 34 Sep 15 15:51 /usr/lib/liblapack.so.3gf -> /etc/alternatives/liblapack.so.3gf

[Andrew Lambe]

I've fixed the problem, though I'm not quite sure what the problem was. I'm posting this in case someone runs into a similar issue.

The fix was to completely uninstall the "redundant" versions of the library (ATLAS, OpenBLAS, etc.) which I had installed to fix other issues. The initial versions of BLAS and LAPACK packaged with Ubuntu are sufficient. I ran a clean build and everything works as expected.