Hi Henrik,
I believe the proper way to handle this is to use the VERSION argument
in the *ax_path_lib_gsl.m4* script.
Unfortunately your modified m4 script seems not to handle versions, and
the original script
https://www.gnu.org/software/autoconf-archive/ax_path_lib_gsl.html
gives me a *4
Building 1808, I got a few errors like:
/usr/bin/ld: apl-QR_factorization_GSL.o: in function
`GSL::QR_factorize_ZZ_matrix(Value&, int, int, Cell const*)':
QR_factorization_GSL.cc:(.text+0x97b): undefined reference to
`gsl_linalg_complex_QR_decomp_r'
Turned out that ./configure was pi
