rotoize' is safe is when you are removing prototypes that were made with `protoize'; if the program worked before without any prototypes, it will work again without them. You can find all the places where this problem might occur by compiling the program with the `-Wtraditional-conversion' option. It prints a warning whenever an argument is converted. * Both conversion programs can be confused if there are macro calls in and around the text to be converted. In other words, the standard syntax for a declaration or definition must not result from expanding a macro. This problem is inherent in the design of C and cannot be fixed. If only a few functions have confusing macro calls, you can easily convert them manually. * `protoize' cannot get the argument types for a function whose definition was not actually compiled due to preprocessing conditionals. When this happens, `protoize' changes nothing in regard to such a function. `protoize' tries to detect such instances and warn about them. You can generally work around this problem by using `protoize' step by step, each time specifying a different set of `-D' options for compilation, until all of the functions have been converted. There is no automatic way to verify that you have got them all, however. * Confusion may result if there is an occasion to convert a function declaration or definition in a region of source code where there is more than one formal parameter list present. Thus, attempts to convert code containing multiple (conditionally compiled) versions of a single function header (in the same vicinity) may not produce the desired (or expected) results. If you plan on converting source files which contain such code, it is recommended that you first make sure that each conditionally compiled region of source code which contains an alternative function header also contains at least one additional follower token (past the final right parenthesis of the function header). This should circumvent the problem. * `unprotoize' can become confused when trying to convert a function definition or declaration which contains a declaration for a pointer-to-function formal argument which has the same name as the function being defined or declared. We recommend you avoid such choices of formal parameter names. * You might also want to correct some of the indentation by hand and break long lines. (The conversion programs don't write lines longer than eighty characters in any case.)  File: gcc.info, Node: Non-bugs, Next: Warnings and Errors, Prev: Protoize Caveats, Up: Trouble 10.10 Certain Changes We Don't Want to Make =========================================== This section lists changes that people frequently request, but which we do not make because we think GCC is better without them. * Checking the number and type of arguments to a function which has an old-fashioned definition and no prototype. Such a feature would work only occasionally--only for calls that appear in the same file as the called function, following the definition. The only way to check all calls reliably is to add a prototype for the function. But adding a prototype eliminates the motivation for this feature. So the feature is not worthwhile. * Warning about using an expression whose type is signed as a shift count. Shift count operands are probably signed more often than unsigned. Warning about this would cause far more annoyance than good. * Warning about assigning a signed value to an unsigned variable. Such assignments must be very common; warning about them would cause more annoyance than good. * Warning when a non-void function value is ignored. C contains many standard functions that return a value that most programs choose to ignore. One obvious example is `printf'. Warning about this practice only leads the defensive programmer to clutter programs with dozens of casts to `void'. Such casts are required so frequently that they become visual noise. Writing those casts becomes so automatic that they no longer convey useful information about the intentions of the programmer. For functions where the return value should never be ignored, use the `warn_unused_result' function attribute (*note Function Attributes::). * Making `-fshort-enums' the default. This would cause storage layout to be incompatible with most other C compilers. And it doesn't seem very important, given that you can get the same result in other ways. The case where it matters most is when the enumeration-valued object is inside a structure, and in that case you can specify a field width explicitly. * Making bit-fields unsigned by default on particular machines where "the ABI standard" says to do so. The ISO C standard leaves it up to the implementation whether a bit-field declared plain `int' is signed or not. This in effect creates two alternative dialects of C. The GNU C compiler supports both dialects; you can specify the signed dialect with `-fsigned-bitfields' and the unsigned dialect with `-funsigned-bitfields'. However, this leaves open the question of which dialect to use by default. Currently, the preferred dialect makes plain bit-fields signed, because this is simplest. Since `int' is the same as `signed int' in every other context, it is cleanest for them to be the same in bit-fields as well. Some computer manufacturers have published Application Binary Interface standards which specify that plain bit-fields should be unsigned. It is a mistake, however, to say anything about this issue in an ABI. This is because the handling of plain bit-fields distinguishes two dialects of C. Both dialects are meaningful on every type of machine. Whether a particular object file was compiled using signed bit-fields or unsigned is of no concern to other object files, even if they access the same bit-fields in the same data structures. A given program is written in one or the other of these two dialects. The program stands a chance to work on most any machine if it is compiled with the proper dialect. It is unlikely to work at all if compiled with the wrong dialect. Many users appreciate the GNU C compiler because it provides an environment that is uniform across machines. These users would be inconvenienced if the compiler treated plain bit-fields differently on certain machines. Occasionally users write programs intended only for a particular machine type. On these occasions, the users would benefit if the GNU C compiler were to support by default the same dialect as the other compilers on that machine. But such applications are rare. And users writing a program to run on more than one type of machine cannot possibly benefit from this kind of compatibility. This is why GCC does and will treat plain bit-fields in the same fashion on all types of machines (by default). There are some arguments for making bit-fields unsigned by default on all machines. If, for example, this becomes a universal de facto standard, it would make sense for GCC to go along with it. This is something to be considered in the future. (Of course, users strongly concerned about portability should indicate explicitly in each bit-field whether it is signed or not. In this way, they write programs which have the same meaning in both C dialects.) * Undefining `__STDC__' when `-ansi' is not used. Currently, GCC defines `__STDC__' unconditionally. This provides good results in practice. Programmers normally use conditionals on `__STDC__' to ask whether it is safe to use certain features of ISO C, such as function prototypes or ISO token concatenation. Since plain `gcc' supports all the features of ISO C, the correct answer to these questions is "yes". Some users try to use `__STDC__' to check for the availability of certain library facilities. This is actually incorrect usage in an ISO C program, because the ISO C standard says that a conforming freestanding implementation should define `__STDC__' even though it does not have the library facilities. `gcc -ansi -pedantic' is a conforming freestanding implementation, and it is therefore required to define `__STDC__', even though it does not come with an ISO C library. Sometimes people say that defining `__STDC__' in a compiler that does not completely conform to the ISO C standard somehow violates the standard. This is illogical. The standard is a standard for compilers that claim to support ISO C, such as `gcc -ansi'--not for other compilers such as plain `gcc'. Whatever the ISO C standard says is relevant to the design of plain `gcc' without `-ansi' only for pragmatic reasons, not as a requirement. GCC normally defines `__STDC__' to be 1, and in addition defines `__STRICT_ANSI__' if you specify the `-ansi' option, or a `-std' option for strict conformance to some version of ISO C. On some hosts, system include files use a different convention, where `__STDC__' is normally 0, but is 1 if the user specifies strict conformance to the C Standard. GCC follows the host convention when processing system include files, but when processing user files it follows the usual GNU C convention. * Undefining `__STDC__' in C++. Programs written to compile with C++-to-C translators get the value of `__STDC__' that goes with the C compiler that is subsequently used. These programs must test `__STDC__' to determine what kind of C preprocessor that compiler uses: whether they should concatenate tokens in the ISO C fashion or in the traditional fashion. These programs work properly with GNU C++ if `__STDC__' is defined. They would not work otherwise. In addition, many header files are written to provide prototypes in ISO C but not in traditional C. Many of these header files can work without change in C++ provided `__STDC__' is defined. If `__STDC__' is not defined, they will all fail, and will all need to be changed to test explicitly for C++ as well. * Deleting "empty" loops. Historically, GCC has not deleted "empty" loops under the assumption that the most likely reason you would put one in a program is to have a delay, so deleting them will not make real programs run any faster. However, the rationale here is that optimization of a nonempty loop cannot produce an empty one. This held for carefully written C compiled with less powerful optimizers but is not always the case for carefully written C++ or with more powerful optimizers. Thus GCC will remove operations from loops whenever it can determine those operations are not externally visible (apart from the time taken to execute them, of course). In case the loop can be proved to be finite, GCC will also remove the loop itself. Be aware of this when performing timing tests, for instance the following loop can be completely removed, provided `some_expression' can provably not change any global state. { int sum = 0; int ix; for (ix = 0; ix != 10000; ix++) sum += some_expression; } Even though `sum' is accumulated in the loop, no use is made of that summation, so the accumulation can be removed. * Making side effects happen in the same order as in some other compiler. It is never safe to depend on the order of evaluation of side effects. For example, a function call like this may very well behave differently from one compiler to another: void func (int, int); int i = 2; func (i++, i++); There is no guarantee (in either the C or the C++ standard language definitions) that the increments will be evaluated in any particular order. Either increment might happen first. `func' might get the arguments `2, 3', or it might get `3, 2', or even `2, 2'. * Making certain warnings into errors by default. Some ISO C testsuites report failure when the compiler does not produce an error message for a certain program. ISO C requires a "diagnostic" message for certain kinds of invalid programs, but a warning is defined by GCC to count as a diagnostic. If GCC produces a warning but not an error, that is correct ISO C support. If testsuites call this "failure", they should be run with the GCC option `-pedantic-errors', which will turn these warnings into errors.  File: gcc.info, Node: Warnings and Errors, Prev: Non-bugs, Up: Trouble 10.11 Warning Messages and Error Messages ========================================= The GNU compiler can produce two kinds of diagnostics: errors and warnings. Each kind has a different purpose: "Errors" report problems that make it impossible to compile your program. GCC reports errors with the source file name and line number where the problem is apparent. "Warnings" report other unusual conditions in your code that _may_ indicate a problem, although compilation can (and does) proceed. Warning messages also report the source file name and line number, but include the text `warning:' to distinguish them from error messages. Warnings may indicate danger points where you should check to make sure that your program really does what you intend; or the use of obsolete features; or the use of nonstandard features of GNU C or C++. Many warnings are issued only if you ask for them, with one of the `-W' options (for instance, `-Wall' requests a variety of useful warnings). GCC always tries to compile your program if possible; it never gratuitously rejects a program whose meaning is clear merely because (for instance) it fails to conform to a standard. In some cases, however, the C and C++ standards specify that certain extensions are forbidden, and a diagnostic _must_ be issued by a conforming compiler. The `-pedantic' option tells GCC to issue warnings in such cases; `-pedantic-errors' says to make them errors instead. This does not mean that _all_ non-ISO constructs get warnings or errors. *Note Options to Request or Suppress Warnings: Warning Options, for more detail on these and related command-line options.  File: gcc.info, Node: Bugs, Next: Service, Prev: Trouble, Up: Top 11 Reporting Bugs ***************** Your bug reports play an essential role in making GCC reliable. When you encounter a problem, the first thing to do is to see if it is already known. *Note Trouble::. If it isn't known, then you should report the problem. * Menu: * Criteria: Bug Criteria. Have you really found a bug? * Reporting: Bug Reporting. How to report a bug effectively. * Known: Trouble. Known problems. * Help: Service. Where to ask for help.  File: gcc.info, Node: Bug Criteria, Next: Bug Reporting, Up: Bugs 11.1 Have You Found a Bug? ========================== If you are not sure whether you have found a bug, here are some guidelines: * If the compiler gets a fatal signal, for any input whatever, that is a compiler bug. Reliable compilers never crash. * If the compiler produces invalid assembly code, for any input whatever (except an `asm' statement), that is a compiler bug, unless the compiler reports errors (not just warnings) which would ordinarily prevent the assembler from being run. * If the compiler produces valid assembly code that does not correctly execute the input source code, that is a compiler bug. However, you must double-check to make sure, because you may have a program whose behavior is undefined, which happened by chance to give the desired results with another C or C++ compiler. For example, in many nonoptimizing compilers, you can write `x;' at the end of a function instead of `return x;', with the same results. But the value of the function is undefined if `return' is omitted; it is not a bug when GCC produces different results. Problems often result from expressions with two increment operators, as in `f (*p++, *p++)'. Your previous compiler might have interpreted that expression the way you intended; GCC might interpret it another way. Neither compiler is wrong. The bug is in your code. After you have localized the error to a single source line, it should be easy to check for these things. If your program is correct and well defined, you have found a compiler bug. * If the compiler produces an error message for valid input, that is a compiler bug. * If the compiler does not produce an error message for invalid input, that is a compiler bug. However, you should note that your idea of "invalid input" might be someone else's idea of "an extension" or "support for traditional practice". * If you are an experienced user of one of the languages GCC supports, your suggestions for improvement of GCC are welcome in any case.  File: gcc.info, Node: Bug Reporting, Prev: Bug Criteria, Up: Bugs 11.2 How and where to Report Bugs ================================= Bugs should be reported to the bug database at `http://bugs.buildroot.net/'.  File: gcc.info, Node: Service, Next: Contributing, Prev: Bugs, Up: Top 12 How To Get Help with GCC *************************** If you need help installing, using or changing GCC, there are two ways to find it: * Send a message to a suitable network mailing list. First try (for help installing or using GCC), and if that brings no response, try . For help changing GCC, ask . If you think you have found a bug in GCC, please report it following the instructions at *note Bug Reporting::. * Look in the service directory for someone who might help you for a fee. The service directory is found at `http://www.gnu.org/prep/service.html'. For further information, see `http://gcc.gnu.org/faq.html#support'.  File: gcc.info, Node: Contributing, Next: Funding, Prev: Service, Up: Top 13 Contributing to GCC Development ********************************** If you would like to help pretest GCC releases to assure they work well, current development sources are available by SVN (see `http://gcc.gnu.org/svn.html'). Source and binary snapshots are also available for FTP; see `http://gcc.gnu.org/snapshots.html'. If you would like to work on improvements to GCC, please read the advice at these URLs: `http://gcc.gnu.org/contribute.html' `http://gcc.gnu.org/contributewhy.html' for information on how to make useful contributions and avoid duplication of effort. Suggested projects are listed at `http://gcc.gnu.org/projects/'.  File: gcc.info, Node: Funding, Next: GNU Project, Prev: Contributing, Up: Top Funding Free Software ********************* If you want to have more free software a few years from now, it makes sense for you to help encourage people to contribute funds for its development. The most effective approach known is to encourage commercial redistributors to donate. Users of free software systems can boost the pace of development by encouraging for-a-fee distributors to donate part of their selling price to free software developers--the Free Software Foundation, and others. The way to convince distributors to do this is to demand it and expect it from them. So when you compare distributors, judge them partly by how much they give to free software development. Show distributors they must compete to be the one who gives the most. To make this approach work, you must insist on numbers that you can compare, such as, "We will donate ten dollars to the Frobnitz project for each disk sold." Don't be satisfied with a vague promise, such as "A portion of the profits are donated," since it doesn't give a basis for comparison. Even a precise fraction "of the profits from this disk" is not very meaningful, since creative accounting and unrelated business decisions can greatly alter what fraction of the sales price counts as profit. If the price you pay is $50, ten percent of the profit is probably less than a dollar; it might be a few cents, or nothing at all. Some redistributors do development work themselves. This is useful too; but to keep everyone honest, you need to inquire how much they do, and what kind. Some kinds of development make much more long-term difference than others. For example, maintaining a separate version of a program contributes very little; maintaining the standard version of a program for the whole community contributes much. Easy new ports contribute little, since someone else would surely do them; difficult ports such as adding a new CPU to the GNU Compiler Collection contribute more; major new features or packages contribute the most. By establishing the idea that supporting further development is "the proper thing to do" when distributing free software for a fee, we can assure a steady flow of resources into making more free software. Copyright (C) 1994 Free Software Foundation, Inc. Verbatim copying and redistribution of this section is permitted without royalty; alteration is not permitted.  File: gcc.info, Node: GNU Project, Next: Copying, Prev: Funding, Up: Top The GNU Project and GNU/Linux ***************************** The GNU Project was launched in 1984 to develop a complete Unix-like operating system which is free software: the GNU system. (GNU is a recursive acronym for "GNU's Not Unix"; it is pronounced "guh-NEW".) Variants of the GNU operating system, which use the kernel Linux, are now widely used; though these systems are often referred to as "Linux", they are more accurately called GNU/Linux systems. For more information, see: `http://www.gnu.org/' `http://www.gnu.org/gnu/linux-and-gnu.html'  File: gcc.info, Node: Copying, Next: GNU Free Documentation License, Prev: GNU Project, Up: Top GNU General Public License ************************** Version 3, 29 June 2007 Copyright (C) 2007 Free Software Foundation, Inc. `http://fsf.org/' Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. 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If additional permissions apply only to part of the Program, that part may be used separately under those permissions, but the entire Program remains governed by this License without regard to the additional permissions. When you convey a copy of a covered work, you may at your option remove any additional permissions from that copy, or from any part of it. (Additional permissions may be written to require their own removal in certain cases when you modify the work.) You may place additional permissions on material, added by you to a covered work, for which you have or can give appropriate copyright permission. Notwithstanding any other provision of this License, for material you add to a covered work, you may (if authorized by the copyright holders of that material) supplement the terms of this License with terms: a. Disclaiming warranty or limiting liability differently from the terms of sections 15 and 16 of this License; or b. Requiring preservation of specified reasonable legal notices or author attributions in that material or in the Appropriate Legal Notices displayed by works containing it; or c. Prohibiting misrepresentation of the origin of that material, or requiring that modified versions of such material be marked in reasonable ways as different from the original version; or d. Limiting the use for publicity purposes of names of licensors or authors of the material; or e. Declining to grant rights under trademark law for use of some trade names, trademarks, or service marks; or f. Requiring indemnification of licensors and authors of that material by anyone who conveys the material (or modified versions of it) with contractual assumptions of liability to the recipient, for any liability that these contractual assumptions directly impose on those licensors and authors. All other non-permissive additional terms are considered "further restrictions" within the meaning of section 10. If the Program as you received it, or any part of it, contains a notice stating that it is governed by this License along with a term that is a further restriction, you may remove that term. If a license document contains a further restriction but permits relicensing or conveying under this License, you may add to a covered work material governed by the terms of that license document, provided that the further restriction does not survive such relicensing or conveying. If you add terms to a covered work in accord with this section, you must place, in the relevant source files, a statement of the additional terms that apply to those files, or a notice indicating where to find the applicable terms. Additional terms, permissive or non-permissive, may be stated in the form of a separately written license, or stated as exceptions; the above requirements apply either way. 8. Termination. You may not propagate or modify a covered work except as expressly provided under this License. Any attempt otherwise to propagate or modify it is void, and will automatically terminate your rights under this License (including any patent licenses granted under the third paragraph of section 11). However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation. Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice. Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, you do not qualify to receive new licenses for the same material under section 10. 9. Acceptance Not Required for Having Copies. You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so. 10. Automatic Licensing of Downstream Recipients. Each time you convey a covered work, the recipient automatically receives a license from the original licensors, to run, modify and propagate that work, subject to this License. You are not responsible for enforcing compliance by third parties with this License. An "entity transaction" is a transaction transferring control of an organization, or substantially all assets of one, or subdividing an organization, or merging organizations. If propagation of a covered work results from an entity transaction, each party to that transaction who receives a copy of the work also receives whatever licenses to the work the party's predecessor in interest had or could give under the previous paragraph, plus a right to possession of the Corresponding Source of the work from the predecessor in interest, if the predecessor has it or can get it with reasonable efforts. You may not impose any further restrictions on the exercise of the rights granted or affirmed under this License. For example, you may not impose a license fee, royalty, or other charge for exercise of rights granted under this License, and you may not initiate litigation (including a cross-claim or counterclaim in a lawsuit) alleging that any patent claim is infringed by making, using, selling, offering for sale, or importing the Program or any portion of it. 11. Patents. A "contributor" is a copyright holder who authorizes use under this License of the Program or a work on which the Program is based. The work thus licensed is called the contributor's "contributor version". A contributor's "essential patent claims" are all patent claims owned or controlled by the contributor, whether already acquired or hereafter acquired, that would be infringed by some manner, permitted by this License, of making, using, or selling its contributor version, but do not include claims that would be infringed only as a consequence of further modification of the contributor version. For purposes of this definition, "control" includes the right to grant patent sublicenses in a manner consistent with the requirements of this License. Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor's essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version. In the following three paragraphs, a "patent license" is any express agreement or commitment, however denominated, not to enforce a patent (such as an express permission to practice a patent or covenant not to sue for patent infringement). To "grant" such a patent license to a party means to make such an agreement or commitment not to enforce a patent against the party. If you convey a covered work, knowingly relying on a patent license, and the Corresponding Source of the work is not available for anyone to copy, free of charge and under the terms of this License, through a publicly available network server or other readily accessible means, then you must either (1) cause the Corresponding Source to be so available, or (2) arrange to deprive yourself of the benefit of the patent license for this particular work, or (3) arrange, in a manner consistent with the requirements of this License, to extend the patent license to downstream recipients. "Knowingly relying" means you have actual knowledge that, but for the patent license, your conveying the covered work in a country, or your recipient's use of the covered work in a country, would infringe one or more identifiable patents in that country that you have reason to believe are valid. If, pursuant to or in connection with a single transaction or arrangement, you convey, or propagate by procuring conveyance of, a covered work, and grant a patent license to some of the parties receiving the covered work authorizing them to use, propagate, modify or convey a specific copy of the covered work, then the patent license you grant is automatically extended to all recipients of the covered work and works based on it. A patent license is "discriminatory" if it does not include within the scope of its coverage, prohibits the exercise of, or is conditioned on the non-exercise of one or more of the rights that are specifically granted under this License. You may not convey a covered work if you are a party to an arrangement with a third party that is in the business of distributing software, under which you make payment to the third party based on the extent of your activity of conveying the work, and under which the third party grants, to any of the parties who would receive the covered work from you, a discriminatory patent license (a) in connection with copies of the covered work conveyed by you (or copies made from those copies), or (b) primarily for and in connection with specific products or compilations that contain the covered work, unless you entered into that arrangement, or that patent license was granted, prior to 28 March 2007. Nothing in this License shall be construed as excluding or limiting any implied license or other defenses to infringement that may otherwise be available to you under applicable patent law. 12. No Surrender of Others' Freedom. If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program. 13. Use with the GNU Affero General Public License. Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such. 14. Revised Versions of this License. The Free Software Foundation may publish revised and/or new versions of the GNU General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. Each version is given a distinguishing version number. If the Program specifies that a certain numbered version of the GNU General Public License "or any later version" applies to it, you have the option of following the terms and conditions either of that numbered version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of the GNU General Public License, you may choose any version ever published by the Free Software Foundation. If the Program specifies that a proxy can decide which future versions of the GNU General Public License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Program. Later license versions may give you additional or different permissions. However, no additional obligations are imposed on any author or copyright holder as a result of your choosing to follow a later version. 15. Disclaimer of Warranty. THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 16. Limitation of Liability. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. 17. Interpretation of Sections 15 and 16. If the disclaimer of warranty and limitation of liability provided above cannot be given local legal effect according to their terms, reviewing courts shall apply local law that most closely approximates an absolute waiver of all civil liability in connection with the Program, unless a warranty or assumption of liability accompanies a copy of the Program in return for a fee. END OF TERMS AND CONDITIONS =========================== How to Apply These Terms to Your New Programs ============================================= If you develop a new program, and you want it to be of the greatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms. To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively state the exclusion of warranty; and each file should have at least the "copyright" line and a pointer to where the full notice is found. ONE LINE TO GIVE THE PROGRAM'S NAME AND A BRIEF IDEA OF WHAT IT DOES. Copyright (C) YEAR NAME OF AUTHOR This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see `http://www.gnu.org/licenses/'. Also add information on how to contact you by electronic and paper mail. If the program does terminal interaction, make it output a short notice like this when it starts in an interactive mode: PROGRAM Copyright (C) YEAR NAME OF AUTHOR This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c' for details. The hypothetical commands `show w' and `show c' should show the appropriate parts of the General Public License. Of course, your program's commands might be different; for a GUI interface, you would use an "about box". You should also get your employer (if you work as a programmer) or school, if any, to sign a "copyright disclaimer" for the program, if necessary. For more information on this, and how to apply and follow the GNU GPL, see `http://www.gnu.org/licenses/'. The GNU General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Lesser General Public License instead of this License. But first, please read `http://www.gnu.org/philosophy/why-not-lgpl.html'.  File: gcc.info, Node: GNU Free Documentation License, Next: Contributors, Prev: Copying, Up: Top GNU Free Documentation License ****************************** Version 1.2, November 2002 Copyright (C) 2000,2001,2002 Free Software Foundation, Inc. 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed. 0. PREAMBLE The purpose of this License is to make a manual, textbook, or other functional and useful document "free" in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others. This License is a kind of "copyleft", which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software. We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference. 1. APPLICABILITY AND DEFINITIONS This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The "Document", below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as "you". You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law. A "Modified Version" of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language. A "Secondary Section" is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document's overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them. The "Invariant Sections" are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none. The "Cover Texts" are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words. A "Transparent" copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not "Transparent" is called "Opaque". Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. Examples of transparent image formats include PNG, XCF and JPG. Opaque formats include proprietary formats that can be read and edited only by proprietary word proc