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Subsections

8.1 Installation

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.

8.1.0.1 ''What Fortran compiler do I need to compile Q-E?''

'''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.

8.1.0.2 ''Why is configure saying that I have no fortran compiler?''

'''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.

8.1.0.3 ''Why is configure saying that my fortran compiler doesn't work?''

'''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.

8.1.0.4 ''configure says 'unsupported architecture', what should I do?''

'''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.

8.1.0.5 ''Why doesn't configure recognize that I have a parallel machine?''

'''A:'''You need a properly configured complete parallel environment. If any piece is missing, configure will revert to serial compilation. In particular:

8.1.0.6 ''Compilation fails with "internal error", what should I do?''

'''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.

8.1.0.7 ''Compilation fails at linking stage: "symbol ... not found"''

'''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 up previous contents
Next: 8.2 Pseudopotentials Up: 8 Frequently Asked Questions Previous: 8 Frequently Asked Questions Contents
Paolo Giannozzi 2010-04-08