Correct issues with netCDF library linking and loading in mesh_tools/grid_rotate
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…tran 4.6.1 In netCDF-Fortran 4.6.1 (at least, as installed on NCAR's Derecho system), the `nf-config --flibs` output includes the netCDF-C library (-lnetcdf), but it does not include the library search path for this library, leading to compilation errors like ld: cannot find -lnetcdf ld: cannot find -lnetcdf As a workaround, this commit adds "-L$(shell nc-config --libdir)" to the definition of FCLIBS in the grid_rotate Makefile.
…rpath On NCAR's Derecho system, compiler wrappers generally handle the setting of rpath for shared libraries in compiled executables. However, the Fortran compiler used in the grid_rotate Makefile is set to the actual compiler used to build the netCDF library using `nf-config --fc`, thereby precluding the use of the compiler wrapper. This leads to runtime issues in locating the netCDF shared libraries, e.g., ./convert_mpas: error while loading shared libraries: libnetcdff.so.7: cannot open shared object file: No such file or directory As a workaround, the grid_rotate Makefile now tries to extract linker rpath flags from the output of `nf-config --flibs` and `nc-config --libs`. These flags are stored in the RPATH_FLAGS make variable, which is then appended to the FCLIBS variable.
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gdicker1
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Feb 28, 2024
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This PR makes changes to the
Makefilefor thegrid_rotatetool to address issues with netCDF library linking and loading.Prior to this PR, the
grid_rotateprogram'sMakefileassumed that the output ofnf-config --flibswas sufficient to provide all library linking flags related to the netCDF library. In netCDF-Fortran 4.6.1, however, thenf-config --flibsoutput includes the netCDF-C library (-lnetcdf), but it does not include the library search path for this library, leading to compilation errors likeAs a workaround, this PR adds
-L$(shell nc-config --libdir)to the definition ofFCLIBSin theMakefile.Even after addressing linking errors, on systems that provide netCDF shared libraries, it was in some cases still necessary
to manually set the
LD_LIBRARY_PATHenvironment variable to ensure that the netCDF libraries could be found by the loader. To work around this issue, theMakefilenow tries to extract linker rpath flags from the output ofnf-config --flibsandnc-config --libs. These flags are stored in theRPATH_FLAGSmake variable, which is then appended to theFCLIBSvariable. With the search paths for the netCDF shared libraries included in thegrid_rotateexecutable, it should no longer be necessary to manipulate theLD_LIBRARY_PATHenvironment variable.