/** \page Page_BuildTroubleshooting Troubleshooting Information
*
* LUFA uses a lot of advanced features of the AVR-GCC compiler, linker, and surrounding binaries. This can sometimes lead to problems compiling applications if one of these
* features is buggy in the version of the tools used in a build environment. Missing utilities and incorrectly set makefile configuration options can also result in different
* errors being produced when compilation or other operations are attempted. The table below lists a set of commonly encountered errors and their resolutions.
*
* <table>
* <tr>
* <th>Problem</th>
* <th>Resolution</th>
* </tr>
* <tr>
* <td>Error "<b><tt>relocation truncated to fit: R_AVR_13_PCREL against symbol <i>{X}</i></tt></b>" shown when compiling.</td>
* <td>Try compiling with the setting <tt>LINKER_RELAXATIONS=N</tt> in your LUFA Build System 2.0 makefile, or remove the line <tt>-Wl,--relax</tt>
* from other makefiles. Alternatively, make sure you have the latest version of the Atmel Toolchain installed for your system.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>error: ld terminated with signal 11 [Segmentation fault]</tt></b>" shown when compiling.</td>
* <td>Try compiling with the setting <tt>DEBUG_LEVEL=2</tt> in your LUFA Build System 2.0 makefile, or make sure you are using <tt>binutils</tt> version 2.22 or later.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>EMERGENCY ABORT: INFINITE RECURSION DETECTED</tt></b>" shown when compiling.</td>
* <td>Make sure you are using an up to date version of GNU Make when compiling. This error is a safety system added to the mid-level makefiles, to prevent an issue with
* GNU make or other variants of Make causing an infinitely recursive build.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>Unsupported architecture "<i>{X}</i>"</tt></b>" shown when compiling.</td>
* <td>Ensure your makefile's <tt>ARCH</tt> setting is set to one of the architecture names (case-sensitive) supported by the version of LUFA you are compiling against.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>Makefile <i>{X}</i> value not set</tt></b>" shown when compiling.</td>
* <td>The specified Makefile value was not configured in your project's makefile or on the command line, and the nominated setting is required by one or more LUFA
* build system modules. Define the value in your project makefile and try again.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>Makefile <i>{X}</i> option cannot be blank</tt></b>" shown when compiling.</td>
* <td>The specified Makefile value was configured in your project's makefile or on the command line, but was set to an empty value. For the nominated configuration
* option, an empty value is not allowed. Define the nominated setting to a correct non-blank value and try again.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>Makefile <i>{X}</i> option must be Y or N</tt></b>" shown when compiling.</td>
* <td>The specified Makefile value was configured in your project's makefile or on the command line, but was set to a value other than a Y (for "Yes") or "N" (for "No").
* This configuration option is required to be one of the aformentioned boolean values, and other values are invalid. Set this option to either Y or N and try again.</td>
* <td>The nominated source files, specified in your project's makefile in the <tt>SRC</tt> configuration option, has an extension that the LUFA build system does not
* recognise. The file extensions are case sensitive, and must be one of the supported formats (<tt>*.c</tt>, <tt>*.cpp</tt> or <tt>*.S</tt>).</td>
* </tr>
* <tr>
* <td>Error "<b><tt>Cannot build with OBJDIR parameter set - one or more object file name is not unique</tt></b>" shown when compiling.</td>
* <td>When a project is built with a non-empty <tt>OBJDIR</tt> object directory name set, all input source files must have unique names, excluding extension and path.
* This means that input files that are named identically and differ only by their path or extension are invalid when this mode is used.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>Source file does not exist: <i>{X}</i></tt></b>" shown when compiling.</td>
* <td>The nominated input source file, specified in the user project's <tt>SRC</tt> parameter, could not be found. Ensure the source file exists and the absolute or
* relative path given in the user project makefile is correct and try again.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>Doxygen configuration file <i>{X}</i> does not exist</tt></b>" shown when upgrading a Doxygen configuration file.</td>
* <td>The nominated Doxygen configuration file, specified in the user project's <tt>DOXYGEN_CONF</tt> parameter, could not be found. Ensure the configuration file exists
* and the absolute or relative path given in the user project makefile is correct and try again, or run the appropriate makefile target to generate a new configuration
* file.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>avr-gcc: error: unrecognized option '<i>{X}</i>'</tt></b>" shown when compiling.</td>
* <td>An unrecognised option was supplied to the compiler, usually in the <tt>C_FLAGS</tt>, <tt>CPP_FLAGS</tt>, <tt>ASM_FLAGS</tt> or <tt>CC_FLAGS</tt> configuration
* options. The nominated compiler switch may be invalid, or unsupported by the version of AVR-GCC on the host system. Remove the unrecognised flag if invalid, or
* upgrade to the latest AVR-GCC. If the option is a valid linker option, use the prefix "-Wl," to ensure it is passed to the linker correctly.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>avr-gcc: error: unrecognized option '<i>{X}</i>'</tt></b>" shown when compiling.</td>
* <td>An unrecognised option was supplied to the compiler, usually in the <tt>C_FLAGS</tt>, <tt>CPP_FLAGS</tt>, <tt>ASM_FLAGS</tt> or <tt>CC_FLAGS</tt> configuration
* options. The nominated compiler switch may be invalid, or unsupported by the version of AVR-GCC on the host system. Remove the unrecognised flag if invalid, or
* upgrade to the latest AVR-GCC. If the option is a valid linker option, use the prefix "-Wl," to ensure it is passed to the linker correctly.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>makefile:{X}: {Y}.mk: No such file or directory</tt></b>" shown when make is invoked.</td>
* <td>The path to the nominated makefile module was incorrect. This usually indicates that the makefile <tt>LUFA_PATH</tt> option is not set to a valid relative or
* absolute path to the LUFA library core.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>makefile:{X}: {Y}.mk: No such file or directory</tt></b>" shown when make is invoked.</td>
* <td>The path to the nominated makefile module was incorrect. This usually indicates that the makefile <tt>LUFA_PATH</tt> option is not set to a valid relative or
* absolute path to the LUFA library core.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>fatal error: LUFAConfig.h: No such file or directory</tt></b>" shown when compiling.</td>
* <td>The <tt>USE_LUFA_CONFIG_HEADER</tt> compile time option was set in the user project makefile, but the user supplied <tt>LUFAConfig.h</tt> header could not be
* found. Ensure that the directory that contains this configuration file is correctly passed to the compiler via the -I switch in the makefile <tt>CC_FLAGS</tt>
* parameter.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>ld.exe: section .apitable_trampolines loaded at <i>{X}</i> overlaps section .text</tt></b>" shown when compiling a bootloader.</td>
* <td>The bootloader is compiling too large for the given <tt>FLASH_SIZE_KB</tt> and <tt>BOOT_SECTION_SIZE_KB</tt> parameters set in the bootloader makefile. This
* usually indicates that these values are incorrect for the specified device the bootloader is targeting. If these values are correct, a newer version of the
* compiler may need to be used to ensure that the bootloader is built within the section size constraints of the target device.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>unknown MCU '<i>{X}</i>' specified</tt></b>" shown when compiling.</td>
* <td>The specified micocontroller device model name set in the user application's makefile as the <tt>MCU</tt> parameter is incorrect, or unsupported by the
* version of the compiler being used. Make sure the model name is correct, or upgrade to the latest Atmel Toolchain to obtain newer device support.</td>
* </tr>
* <tr>
* <td>Error "<b><tt>error: invalid suffix "x" on integer constant</tt></b>" shown when compiling a bootloader.</td>
* <td>This is usually caused by the <tt>bc.exe</tt> application not being found in the system's <tt>PATH</tt> variable. Make sure you have the <tt>bc.exe</tt> tool
* installed correctly (see \ref Sec_Prerequisites).</td>
* </tr>
* <tr>
* <td>Error "<b><tt>undefined reference to `<i>{X}</i>'</tt></b>" shown when compiling.</td>
* <td>This is usually caused by a missing source file in the user application's <tt>SRC</tt> configuration parameter. If the indicated symbol is one from the LUFA
* library, you may be missing a LUFA source makefile module (see \ref Page_BuildModule_SOURCES).</td>
* </tr>
* </table>
*
* For troubleshooting other errors you encounter, please see \ref Sec_ProjectHelp.
