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Subsections
Most installation problems have obvious origins and can be solved by reading
error messages and acting accordingly. Sometimes the reason for a failure
is less obvious. In such a case, you should look into the Installation
Issues section of the User Guide, and into the pw_forum archive to
see if a similar problem (with solution) is described. If you get
really weird error messages during installation, look for them with
your preferred Internet search engine (such as Google): very often you
will find an explanation and a workaround.
'''A:''' Any non-buggy, or not-too-buggy, fortran-95 compiler should work,
with minimal or no changes to the code. configure may not be able to
recognize your system, though.
'''A:'''Because you haven't one (really!); or maybe you have one, but it is
not your execution path; or maybe it has been given an unusual name by your
system manager. Install a compiler if you have none; if you have one, fix
your execution path, or define an alias if it has a strange name.
'''A:''' Because it doesn't work. Really! More exactly, configure has tried
to compile a small test program and didn't succeed. Your compiler may not be
properly installed. For Intel compiler on PC's: you may have forgotten to run
the required initialization script for the compiler.
'''A:''' If compilation/linking still works, never mind, Otherwise,
supply a suitable
supported architecture to configure: see instructions in README.configure on
what to do. Note that in most cases you may use configure to produce dependencies,
then edit the file make.sys.
'''A:'''You need a properly configured complete parallel
environment. If any piece is missing, configure will revert to serial
compilation. In particular:
- configure tries to locate a parallel compiler in a logical
place with a logical name, but if it has a strange names or it is
located in a strange location, you will have to instruct configure
to find it. Note that in most PC clusters (Beowulf), there is no
parallel Fortran-95 compiler in default installations: you have to
configure an appropriate script, such as mpif90.
- configure tries to locate libraries (both mathematical and
parallel libraries) in logical places with logical names, but if
they have strange names or strange locations, you will have to
rename/move them, or to instruct configure to find them (see
subsection "Libraries"). Note that if MPI libraries are not found,
parallel compilation is disabled.
- configure tests that the compiler and the libraries are
compatible (i.e. the compiler may link the libraries without
conflicts and without missing symbols). If they aren't and the
compilation fail, configure will revert to serial compilation.
'''A:''' Any message saying something like "internal compiler error" means
that your compiler is buggy. If you paid real money for your compiler,
complain with the software vendor. If not: sometimes reducing the optimization
level will do the trick, sometimes rearranging the code solves the problem,
but most often you will need to update your compiler to a less buggy version.
'''A:''' If the missing symbols (i.e. routines that are called but not found)
are in the code itself: most likely the fortran-to-C conventions used
in file include/c_defs.h are not appropriate. Change them and retry.
If the missing symbols are in external libraries (Blas, Lapack, FFT,
MPI libraries):
there is a name mismatch between what the compiler expects and what the
library provides. This case is described in detail in the User Guide.
If the missing symbols aren't found anywhere either in the code or in the
libraries: they are system library symbols. i) If they are called by external
libraries, you need to add a missing system library, or to use a different
set of external libraries, compiled with the same compiler you are using.
ii) If you are using no external libraries and still getting missing symbols,
your compiler and compiler libraries are not correctly installed.
Next: 8.2 Pseudopotentials
Up: 8 Frequently Asked Questions
Previous: 8 Frequently Asked Questions
Contents
Paolo Giannozzi
2010-04-08