Link error when compiling NCZhdf5filters.o on MinGW64 with netCDF 4.9.0

[Alexander-Barth]

I am still trying to update NetCDF for Julia users on Windows. In this test, I tried native compilation on Windows (using the MinGW64 toolchain from MSYS2).

NetCDF is configured as:

./configure --disable-testsets  --enable-shared  --disable-static  --disable-dap-remote-tests
make LDFLAGS=" -no-undefined -Wl,--export-all-symbols"

The MinGW64 compiler version is:

$ gcc --version
gcc.exe (Rev2, Built by MSYS2 project) 12.1.0
Copyright (C) 2022 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

The full error message is:

make[3]: Entering directory '/home/Alexander Barth/netcdf-c-2/plugins'
/bin/sh ../libtool  --tag=CC   --mode=link gcc  -fno-strict-aliasing   -module -avoid-version -shared -export-dynamic -rpath /home/Alexander Barth/netcdf-c-2/plugins -no-undefined -no-undefined -Wl,--export-all-symbols -o lib__nczhdf5filters.la -rpath /home/Alexander Barth/netcdf-c-2/plugins/plugindir NCZhdf5filters.lo  -lhdf5_hl -lhdf5 -lm -lz -lsz -lbz2 -lzstd -lxml2 -lcurl
libtool: link: rm -fr  .libs/lib__nczhdf5filters.dll.a
libtool: link: gcc -shared  .libs/NCZhdf5filters.o   -lhdf5_hl -lhdf5 -lz -lsz -lbz2 -lzstd -lxml2 -lcurl  -Wl,--export-all-symbols   -o .libs/lib__nczhdf5filters.dll -Wl,--enable-auto-image-base -Xlinker --out-implib -Xlinker .libs/lib__nczhdf5filters.dll.a
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/12.1.0/../../../../x86_64-w64-mingw32/bin/ld.exe: .libs/NCZhdf5filters.o:NCZhdf5filters:(.text+0x1a24): undefined reference to `nc_inq_var'
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/12.1.0/../../../../x86_64-w64-mingw32/bin/ld.exe: .libs/NCZhdf5filters.o:NCZhdf5filters:(.text+0x1a5a): undefined reference to `nc_inq_type'
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/12.1.0/../../../../x86_64-w64-mingw32/bin/ld.exe: .libs/NCZhdf5filters.o:NCZhdf5filters:(.text+0x2350): undefined reference to `nc_inq_var'
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/12.1.0/../../../../x86_64-w64-mingw32/bin/ld.exe: .libs/NCZhdf5filters.o:NCZhdf5filters:(.text+0x2386): undefined reference to `nc_inq_type'
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/12.1.0/../../../../x86_64-w64-mingw32/bin/ld.exe: .libs/NCZhdf5filters.o:NCZhdf5filters:(.text+0x2423): undefined reference to `nc_inq_dimlen'
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/12.1.0/../../../../x86_64-w64-mingw32/bin/ld.exe: .libs/NCZhdf5filters.o:NCZhdf5filters:(.text+0x245a): undefined reference to `nc_inq_var_chunking'
C:/msys64/mingw64/bin/../lib/gcc/x86_64-w64-mingw32/12.1.0/../../../../x86_64-w64-mingw32/bin/ld.exe: .libs/NCZhdf5filters.o:NCZhdf5filters:(.text+0x24ee): undefined reference to `nc_inq_var_endian'
collect2.exe: error: ld returned 1 exit status
make[3]: *** [Makefile:872: lib__nczhdf5filters.la] Error 1
make[3]: Leaving directory '/home/Alexander Barth/netcdf-c-2/plugins'
make[2]: *** [Makefile:731: all] Error 2
make[2]: Leaving directory '/home/Alexander Barth/netcdf-c-2/plugins'
make[1]: *** [Makefile:764: all-recursive] Error 1
make[1]: Leaving directory '/home/Alexander Barth/netcdf-c-2'
make: *** [Makefile:609: all] Error 2

These steps worked when compiling NetCDF 4.8.1 on the same machine.

It might be related to the LDFLAGS passed to make, which is also used here: https://github.com/Unidata/netcdf-c/blob/main/.github/workflows/run_tests_win_mingw.yml#L49

Any help would be greatly appreciated!

Maybe this is related: https://github.com/Unidata/netcdf-c/issues/2419

[WardF]

With the 4.6.0 Fortran release out the door, I am pivoting back to this and other issues we're seeing with the 4.9.0 release. I'll see if I can get this figured out and fixed, I want the release cycle for 4.9.1 to be a very short one.

[Alexander-Barth]

Would it be possible to enable plugins in the MinGW CI tests? And possibly also byte range support?

https://github.com/Unidata/netcdf-c/blob/main/.github/workflows/run_tests_win_mingw.yml#L38

[WardF]

I don't recall why they are disabled to begin with, so let's start by taking a look at what happens if we turn them on.

[WardF]

@Alexander-Barth I'm curious, do you run into issues when trying to enable plugins or byterange? I am struggling to get things working, even just with the byterange, in a fresh MSYS2/MinGW64 environment. Starting with byterange, I've been able to eventually get things to compile using pkg-config libcurl --libs and pkg-config libcurl --cflags, but I then observe really odd crashes when I try to use any of the resultant executables. I confess this isn't my usual test/work environment, and if I am making a mistake that's easy to fix, I'd be glad to know about it. I'm able to replicate what's in the MinGW GitHub actions workflow script successfully, no problem.

[DWesl]

I have plugins building with Autotools here, but hadn't tried byterange. I'm waiting on test results to see what happens. (EDIT: enabling byterange and DAP on MinGW autotools build passes)

I think the big thing with MinGW plugins is that LDADD only works for PROGRAMS targets, not LTLIBRARIES targets; you need to add libnetcdf.la to each program's _LIBADD variable (programs use LDADD, libraries use LIBADD)