-lcurl included in libraries, even when remote access disabled

[edwardhartnett]

I got this email from a NOAA programmer:

I am trying to run the model on a new system and I compiled all libraries on login node, but when I run the regression tests on compute nodes, where we also run the build steps, compilation fails with the error about missing libcurl library.

ld: cannot find -lcurl

Compute nodes are probably configured slightly differently than login nodes.

I found that the -lcurl linker flag comes from the netcdf library, specifically:

[Dusan.Jovic@nfe04 install]$ grep -r lcurl netcdf
netcdf/lib/libnetcdf.settings:Extra libraries: -lm -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm
netcdf/lib/libnetcdf.la:dependency_libs=' -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/hdf5/lib -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/zstd/lib
-L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/zlib/lib -lstdc++ -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm'
netcdf/lib/pkgconfig/netcdf.pc:Libs: -L${libdir} -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/hdf5/lib -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/z
std/lib -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/zlib/lib -lnetcdf -lm -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm
netcdf/lib/pkgconfig/netcdf.pc:Libs.private: -lm -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm
netcdf/lib/libnetcdff.la:dependency_libs=' -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/hdf5/lib -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/netcdf/
lib -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/zstd/lib -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/zlib/lib /collab1/data/Dusan.Jovic/sufs/simple
-ufs/libs/ufslibs/install/netcdf/lib/libnetcdf.la -lstdc++ -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm'
netcdf/bin/nc-config:libs="-L${libdir} -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/hdf5/lib -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/zstd/lib -L
/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/zlib/lib -lnetcdf -lm -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm"
netcdf/bin/nc-config:libsprivate="-lm -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm"

I do not see '-ldisable-curl' or '-disable-libcurl' option. I am using '-disable-dap' among other options, like '-enable-netcdf-4' etc and i thought that disabling dap will disable libcurl. Is there any other option I need to specify to remove dependency on libcurl.

So we need a way to build without lcurl, even if curl is present.

[akrherz]

Is this fixed by #2907 ?

[WardF]

It should be; if you check v4.9.3-rc1 and see it is still happening, let me know, otherwise this should be fixed. I'll also go take another look just to make sure.

[edwardhartnett]

Ok, I compiled 4.9.3.-rc1, and I still see -lcurl in netcdf.pc

[Dusan.Jovic@nfe04 netcdf]$ cat lib/pkgconfig/netcdf.pc
prefix=/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/netcdf
exec_prefix=${prefix}
libdir=/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/netcdf/lib
includedir=${prefix}/include
ccompiler=/apps/spack-2024-08-26/linux-rocky9-x86_64/oneapi-2024.2.0/intel-oneapi-mpi-2021.13.1-xlclnymo5yndi44r7a7ekefsiym72jyl/mpi/2021.13/bin/mpiicx

Name: netcdf-c
Description: NetCDF Client Library for C
URL: https://www.unidata.ucar.edu/netcdf
Version: 4.9.3-rc1
Libs: -L${libdir} -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/hdf5/lib -L/collab1/data/Dusan.Jovic/sufs/simple-ufs/libs/ufslibs/install/zstd/lib -L/collab1/data/Dusan.J
ovic/sufs/simple-ufs/libs/ufslibs/install/zlib/lib -lnetcdf -lm -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm
Libs.private: -lm -lcurl -lhdf5_hl -lhdf5 -lzstd -lz -lm
Cflags: -I${includedir}

In the PR mentioned in your issue (#2907) I see they fixed only cmake not configure.

[WardF]

Thanks, taking a look at this in autoconf-based builds now.