[netCDF #XNR-979092]: Problems building Netcdf 4.0 or 3.6.3 on 64-bit

>
> Hi,
>
> It seems that the problem mentioned at:
>
>
http://www.unidata.ucar.edu/software/netcdf/docs/known_symptoms.html#NF_INT_IS_C
>
> is not limited to the intel compiler.  I had the same problem with
> gfortran/gcc version 4.2.2 on an x86_64 system.
>

This is a well-tested combination, so you should be able to do this no
problem.

> I'm building with:
>
> CC=/local/bin/gcc
> FC=/local/bin/gfortran
> F77=/local/bin/gfortran
> F90=
> CFLAGS=-fPIC -Df2cFortran
> FFLAGS=-fPIC
> F90FLAGS=-fPIC
> CXXFLAGS=-fPIC
> CXX=/home/local/gcc/bin/g++

Don't bother setting F90 or F77, just set FC=gfortran. (It would be best to put
local/bin in your path instead of using it as part of the compiler name, but I
think it should still work.)

Set CXX='' to stop the C++ API build and test.

Don't set -fPIC anywhere. Instead, use --enable-shared in the configure file.
It will set the correct options for your compilers (which probably will end up
being -fPIC, but may also involve other stuff).

Don't set f2cFortran in CPPFLAGS. Just let configure try to figure out what to
set. As I recall, it depends on your version of gfortran - they changed their
default name mangling around version 4.2.

>
> ./configure --enable-netcdf-4 --disable-f90 --with-hdf5=/home/local/opt
--with-zlib=/home/local/opt --with-szlib=/home/local/opt

Did you really mean to disable F90?

If this is for ncl, and you only use the C API, you could just do --disable-f77
--disable-cxx, and build just the C API (and utilities and examples). Then you
can forget this fortran stuff! ;-)

>
> I've attached the output from configure, make, and config.log.
>
> Note the problems with "g++". Does this affect the "fortran" part of
> the build? I tried building with --disable-cxx, but it then tried to
> use "c++".  I don't need the C++  interface.

Let's solve the fortran first, and if you want C++, we'll do that next. It's
completely separate. But you will need a 64-bit capable version of c++. In
fact, it should be part of your gcc package, and so if your gcc is 64-bit ,
then so is c++, unless you have some funny problem for your sysadmin to sort
out.

The symptom of your problem is here:
checking for Fortran "byte"... yes
checking for Fortran "integer*2"... yes
checking if Fortran "byte" is C "signed char"... no
checking if Fortran "byte" is C "short"... no
checking if Fortran "byte" is C "int"... no
checking if Fortran "byte" is C "long"... no
checking if Fortran "integer*2" is C "short"... no
checking if Fortran "integer*2" is C "int"... no
checking if Fortran "integer*2" is C "long"... no
checking if Fortran "integer" is C "int"... no
checking if Fortran "integer" is C "long"... no
checking if Fortran "real" is C "float"... no
checking if Fortran "real" is C "double"... no
checking if Fortran "doubleprecision" is C "double"... no
checking if Fortran "doubleprecision" is C "float"... no

These cannot all be "no"!

Looking in config.log, I see:

configure:24070: /local/bin/gcc -c  -fPIC -Df2cFortran conftest.c
conftest.c: In function 'sub_':
conftest.c:4: warning: incompatible implicit declaration of built-in function
'exit'
configure:24073: $? = 0
configure:24076: /local/bin/gfortran -fPIC -c conftestf.f
configure:24079: $? = 0
configure:24082: /local/bin/gfortran -o conftest -fPIC  conftestf.o conftest.o
configure:24085: $? = 0
configure:24088: ./conftest
./conftest: error while loading shared libraries: libgfortran.so.2: wrong ELF 
class: ELFCLASS32

So there are two problems. The second is caused because libgfortran.so.2 is the
32-bit version. Do you have to provide the -m64 option to gfortran? I don't
know (but set it in FCFLAGS and FFLAGS if you want to try it). But I seem to
recall I had to find the 64-bit version of libgfortran and set my
LD_LIBRARY_PATH to include that directory. (Or set LDFLAGS, but you will need
to do that for every fortran program you build with netcdf, whereas
LD_LIBRARY_FLAGS works for everything.)

The first problem, concerning the exit function, might be because you have
specified -fPIC.

So try it again, with just CC and FC set, using --enable-shared, and let me
know if it still doesn't work.

Thanks,

Ed

Ticket Details
===================
Ticket ID: XNR-979092
Department: Support netCDF
Priority: Normal
Status: Closed