Frequently Asked Questions

Table of contents

Q01: | Why the name SmallEiffel The GNU Eiffel Compiler?
Q02: | What's the matter with version numbering?
Q03: | Is it possible to have the complete Eiffel source code of SmallEiffel?
Q04: | Is it possible to use SmallEiffel for large/commercial applications?
Q05: | Is it possible to do incremental compilation with SmallEiffel?
Q06: | Is there a SmallEiffel mailing list?
Q07: | What about the Guru section?
Q08: | Is it difficult to switch from ISE to SmallEiffel?
Q09: | Are there mirror FTP sites for SmallEiffel?
Q10: | Is it possible to use the Boehm-Demers-Weiser garbage collector with SmallEiffel?
Q11: | Why don't you post more messages in newsgroups and/or mailing lists?
Q12: | It is possible to create applets with `compile_to_jvm`?
Q13: | Where do I send bug reports?
Q14: | Is there a mechanism to precompile libraries?
Q15: | How is SmallEiffel compiled?
Q16: | How do I keep informed about SmallEiffel?
Q17: | What documentation is provided with SmallEiffel? Where can I find Eiffel documentation?
Q18: | Does SmallEiffel compile the whole Eiffel language ?
Q19: | How can I help ?
Q20: | Why don't you change this and add that?! It would be much better/cooler/whatever !
Q21: | How to customize the Garbage Collector for a new architecture ?

Questions and answers

Q01: | Why the name SmallEiffel The GNU Eiffel Compiler?
A01: | SmallEiffel comes from the mixing of the names Smalltalk and Eiffel. Our aim is to offer an Eiffel development environment as easy to use as Smalltalk and as safe as Eiffel. Since version -0.82, SmallEiffel has been promoted by the Free Software Foundation the official GNU Eiffel Compiler.
Q02: | What's the matter with version numbering?
A02: | Version numbering uses negative numbers. The first distributed version was numbered -0.99, the second one -0.98, the third -0.97, and so on. Version number -0.0 should correspond to the very best Eiffel compiler on this planet :-)
Q03: | Is it possible to have the complete Eiffel source code of SmallEiffel?
A03: | Since it is the GNU Eiffel Compiler, the complete source code of SmallEiffel is of course in the distribution. The source code for additional libraries is also provided.
Q04: | Is it possible to use SmallEiffel for large/commercial applications?
A04: | It is very possible to use SmallEiffel for a large application. An Eiffel compiler is a really big project and SmallEiffel itself is fully written in Eiffel. SmallEiffel is completely free and any private compagny can use SmallEiffel freely, and distribute freely the products made with it. They do not have to pay royalties. However, SmallEiffel doesn't come with any warranty (please read the COPYING file in the distribution). For extended support as well as consulting, see here.
Q05: | Is it possible to do incremental compilation with SmallEiffel?
A05: | Before release -0.91 the answer was no. The answer is now YES. Because of the SmallEiffel type inference mechanism, SmallEiffel always produces all needed C files from scratch. As old C files are automatically saved, only modified C files are recompiled. See `man/compile` for details.
Q06: | Is there a SmallEiffel mailing list?
A06: | Yes! SmallEiffel users and developpers can share their experiences and ideas by subscribing to the SmallEiffel official mailing list.
Q07: | What about the Guru section?
A07: | Some feature section of the SmallEiffel library are labelled with : `feature -- The Guru section :` If you really need your software to be portable on other Eiffel compilers, do not use those features.
Q08: | Is it difficult to switch from ISE to SmallEiffel?
A08: | If your original ISE software only uses simple types like INTEGER, STRING, ARRAY, BOOLEAN, CHARACTER and DOUBLE, it is usually very simple. It is a little bit difficult for simple input/output (used with predefined `io') because some features have different names. If your original software heavily relies on the EiffelBase library, it may be very difficult. For example, one must keep in mind that SmallEiffel.ARRAY inherit SmallEiffel.COLLECTION and that ISE library also have a class COLLECTION. By the way, subclasses of ISE.COLLECTION cannot be used. The ISE.LINKED_LIST can be used in conjunction with SmallEiffel.ARRAY because ISE.LINKED_LIST do not inherit ISE.COLLECTION (no clash).
Q09: | Are there mirror FTP sites for SmallEiffel?
A09: | Australia ftp://ftp.progsoc.uts.edu.au/pub/Eiffel/SmallEiffel/ Austria http://gd.tuwien.ac.at/pub/languages/SmallEiffel/ USA ftp://ftp.cs.rit.edu/pub/mirrors/SmallEiffel/
Q10: | Is it possible to use the Boehm-Demers-Weiser garbage collector with SmallEiffel?
A10: | Yes. You just have to disable the generation of the GC by SmallEiffel (option -no_gc) and replace it by the BDW library. Note that the BDW GC can be easily added because SmallEiffel only uses malloc/realloc/calloc. You can download the BDW library from : http://reality.sgi.com/boehm_mti/gc_source How to integrate the Boehm-Demers-Weiser garbage collector with SmallEiffel (from a message of Dietmar Wolz) : Make the `gc.a` file from the BDW package. Then move this `gc.a` file to `/usr/lib/libgc.a`. Move `gc.h` the to working directory and add the following lines: `#define malloc(n) GC_malloc(n)` `#define calloc(m,n) GC_malloc((m)*(n))` `#define realloc(p,n) GC_realloc((p),(n))` `#define free(p) GC_free(p)` instead of calling `"compile -o executable -boost -O root"` now call `"compile -o executable -boost -O root -no_gc -lgc -include gc.h`
Q11: | Why don't you post more messages in newsgroups and/or mailing lists?
A11: | First, because we strongly believe that too much information kills information. Scientists call this "cognitive overload". :) Second, because we don't have the time. It takes an awful amount of time to follow discussions, whichever their quality. We try to do that. But it's even more time-consuming to be part of them. So, we often have too choose betwen posting/mailing, and working directly on SmallEiffel. Since our mailboxes tend to overflood, we generally choose the latter :)
Q12: | It is possible to create applets with `compile_to_jvm`?
A12: | Not yet. SmallEiffel was designed to compile Eiffel applications to C code or Java bytecode, but not applets.
Q13: | Where and how do I send bug reports?
A13: | Before sending any bug report, please: Compile your application with the `-verbose` flag, without the `-no_warning` flag, and with all assertions on (default mode, or `-all_check` flag). This may reveal a problem in the code you're trying to compile rather than in SmallEiffel... Check that you've got the latest version of SmallEiffel. Check that the bug has not been fixed in our latest (beta or working) version Verify that is it not a known problem by looking at our "not yet implemented" page Check whether the problem has not already been reported in the SmallEiffel mailing-list A good and useful bug report -- that is, one that is more likely to be fixed -- is one that respects the following simple guideline: BE PRECISE . More precisely ;-) : Which hardware architecture do you use ? What operating system and which version of it ? What is your version of SmallEiffel ? Your C compiler or JVM, and its version ? Tell us how to reproduce the problem. Try to isolate it on a small program and send us the latter with all instructions necessary in order for us to reproduce the problem. Don't forget to tell us the compilation command you used. If for any reason you can't send us the small program mentionned above, things may be much more difficult for us. So give us all the releavant information you have. The compilation command line that creates the problem (once again, preferably, with the `-verbose` flag, without the `-no_warning` flag, and with all assertions on -- default mode, or `-all_check` flag) and its verbose output. The execution stack trace you get in case of a crash. Whether the problem occurs with any assertion level or not. Whether the GC is concerned (try with and w/o the `-no_gc` flag). Bug reports can be sent either to Dominique.Colnet@loria.fr and Olivier.Zendra@loria.fr, or to the SmallEiffel mailing-list. Don't worry if you don't get an ack: we don't send them because it takes time, but we store all the bug reports we receive. And we even try to fix them ASAP! :)
Q14: | Is there a mechanism to precompile libraries?
A14: | No, there is no such mechanism in SmallEiffel. But if you're concerned about speed, don't worry, precomputed libraries are not the only way to be fast ! Just try SmallEiffel, and you'll see :)
Q15: | How is SmallEiffel compiled?
A15: | With Eiffel optimization options -boost and -no_gc. The garbage collector is indeed useless on the SmallEiffel commands: since SmallEiffel did not include a GC in its first versions, we were very careful about memory when we developped it. With C compilation optimizations turned on (it depends on the C compiler used; we generally use GCC). The resulting executables are stripped.
Q16: | How do I keep well informed about SmallEiffel?
A16: | The best way is to keep an eye on our web pages, more especially on the What's New? page and the History of Changes. People who want detailed information may also decide to stay tuned to the SmallEiffel mailing-list.
Q17: | What documentation is provided with SmallEiffel? Where can I find Eiffel documentation?
A17: | The documentation provided with SmallEiffel is a transcript of what you can find on the original SmallEiffel Web site, at http://SmallEiffel.loria.fr. It is related only to the use and internals of SmallEiffel (yes, we know we still have to improve it ;) ). For information and documentation about the Eiffel language, check the links on our Internet resources page. Note that we are not aware of any complete Eiffel language manual freely available on the Web (yet?).
Q18: | Does SmallEiffel compile the whole Eiffel language ?
A18: | Yes. "Small" in SmallEiffel does not mean that a subset of the language is used. See the question about the SmallEiffel name.
Q19: | How can I help ?
A19: | The best way to help SmallEiffel and its users is probably to pick up some area you're interested in, and develop with SmallEiffel your own library, application, tool, extension, etc., releasing it to other users. To avoid duplicate efforts, we suggest you have a look to what other people are already doing around SmallEiffel and help them if something that's of interest to you is already under work. There are actually very good things in there, some we were not even aware of, when they were under development ! :) Another very good way to help us is to follow the bug report guidelines when you find some problem with SmallEiffel :)) Finally, you may also consider funding the development of particular features you wouls like to have.
Q20: | Why don't you change this and add that?! It would be much better/cooler/whatever !
A20: | People must understand that we can't always do everything. We simply can't. Because we don't have the time. Whether we like it or not, we also have other things to do than provide free stuff, modify our compiler and/or libraries to please everybody. We do as much as we can, but we don't do miracles, sorry. Since SmallEiffel is free of charge and open-source, people who do need things we don't provide can always implement them and have them benefit everybody. A good way to do this is to start working on it, and ask other people (i.e. not the SmallEiffel team ;) ) to join and help. See the "How can I help ?" question. Alternatively, someone or some company who does need us to implement something may always consider funding a bit the development of SmallEiffel... After all, we've even heard that some people were selling sofware and making a bit of money with it... ;)))
Q21: | How to customize the Garbage Collector for a new architecture ?
A21: | The `install` command is supposed to tune the GC automatically for you. Unfortunately, on some systems, this is not yet automatic. Here the way to fix your installation manually (hence to provide a patch for the install command itself). The content of file `SmallEiffel/sys/gc` indicates the appropriate `mark_stack_and_registers' C function for your system. As an example, if the file `SmallEiffel/sys/gc` contains on the very first line the name linux.c, the file `SmallEiffel/sys/gc_lib/linux.c` is used to get the appropriate definition of the `mark_stack_and_registers' C function. This definition is automatically included in the generated C files (use the -verbose flag to check for the path of the selected `gc_lib` file). If the very first line of the file `SmallEiffel/sys/gc` is NONE, the compiler will continue to emit a warning about GC configuration and will use the default `SmallEiffel/sys/gc_lib/generic.c` definition. To fix this, you have to select the appropriate file of the `SmallEiffel/sys/gc_lib` directory and update `SmallEiffel/sys/gc` accordingly. In order to check the GC, you should be able to run all files of the `SmallEiffel/misc/benchmarks/gc directory`. If you don't find an appropriate file for your system in the `SmallEiffel/sys/gc_lib` directory, you should first check that the `generic.c` definition works. The `generic.c` file contains some more information to allow you to write your own new configuration.

Copyright © Dominique COLNET and Suzanne COLLIN - <colnet@loria.fr>
Last update: 26 November 2000, by DC.