1<html lang="en"> 2<head> 3<title>Bug Reporting - Untitled</title> 4<meta http-equiv="Content-Type" content="text/html"> 5<meta name="description" content="Untitled"> 6<meta name="generator" content="makeinfo 4.13"> 7<link title="Top" rel="start" href="index.html#Top"> 8<link rel="up" href="Reporting-Bugs.html#Reporting-Bugs" title="Reporting Bugs"> 9<link rel="prev" href="Bug-Criteria.html#Bug-Criteria" title="Bug Criteria"> 10<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 11<!-- 12This file documents the GNU linker LD 13(Sourcery CodeBench Lite 2013.11-24) 14version 2.23.52. 15 16Copyright (C) 1991-2013 Free Software Foundation, Inc. 17 18Permission is granted to copy, distribute and/or modify this document 19under the terms of the GNU Free Documentation License, Version 1.3 20or any later version published by the Free Software Foundation; 21with no Invariant Sections, with no Front-Cover Texts, and with no 22Back-Cover Texts. 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If you obtained <samp><span class="command">ld</span></samp> from a support organization, we 52recommend you contact that organization first. 53 54 <p>You can find contact information for many support companies and 55individuals in the file <samp><span class="file">etc/SERVICE</span></samp> in the <span class="sc">gnu</span> Emacs 56distribution. 57 58 <p>Otherwise, send bug reports for <samp><span class="command">ld</span></samp> to 59<a href="https://sourcery.mentor.com/GNUToolchain/">https://sourcery.mentor.com/GNUToolchain/</a>. 60 61 <p>The fundamental principle of reporting bugs usefully is this: 62<strong>report all the facts</strong>. If you are not sure whether to state a 63fact or leave it out, state it! 64 65 <p>Often people omit facts because they think they know what causes the 66problem and assume that some details do not matter. Thus, you might 67assume that the name of a symbol you use in an example does not 68matter. Well, probably it does not, but one cannot be sure. Perhaps 69the bug is a stray memory reference which happens to fetch from the 70location where that name is stored in memory; perhaps, if the name 71were different, the contents of that location would fool the linker 72into doing the right thing despite the bug. Play it safe and give a 73specific, complete example. That is the easiest thing for you to do, 74and the most helpful. 75 76 <p>Keep in mind that the purpose of a bug report is to enable us to fix 77the bug if it is new to us. Therefore, always write your bug reports 78on the assumption that the bug has not been reported previously. 79 80 <p>Sometimes people give a few sketchy facts and ask, “Does this ring a 81bell?” This cannot help us fix a bug, so it is basically useless. We 82respond by asking for enough details to enable us to investigate. 83You might as well expedite matters by sending them to begin with. 84 85 <p>To enable us to fix the bug, you should include all these things: 86 87 <ul> 88<li>The version of <samp><span class="command">ld</span></samp>. <samp><span class="command">ld</span></samp> announces it if you start it with 89the ‘<samp><span class="samp">--version</span></samp>’ argument. 90 91 <p>Without this, we will not know whether there is any point in looking for 92the bug in the current version of <samp><span class="command">ld</span></samp>. 93 94 <li>Any patches you may have applied to the <samp><span class="command">ld</span></samp> source, including any 95patches made to the <code>BFD</code> library. 96 97 <li>The type of machine you are using, and the operating system name and 98version number. 99 100 <li>What compiler (and its version) was used to compile <samp><span class="command">ld</span></samp>—e.g. 101“<code>gcc-2.7</code>”. 102 103 <li>The command arguments you gave the linker to link your example and 104observe the bug. To guarantee you will not omit something important, 105list them all. A copy of the Makefile (or the output from make) is 106sufficient. 107 108 <p>If we were to try to guess the arguments, we would probably guess wrong 109and then we might not encounter the bug. 110 111 <li>A complete input file, or set of input files, that will reproduce the 112bug. It is generally most helpful to send the actual object files 113provided that they are reasonably small. Say no more than 10K. For 114bigger files you can either make them available by FTP or HTTP or else 115state that you are willing to send the object file(s) to whomever 116requests them. (Note - your email will be going to a mailing list, so 117we do not want to clog it up with large attachments). But small 118attachments are best. 119 120 <p>If the source files were assembled using <code>gas</code> or compiled using 121<code>gcc</code>, then it may be OK to send the source files rather than the 122object files. In this case, be sure to say exactly what version of 123<code>gas</code> or <code>gcc</code> was used to produce the object files. Also say 124how <code>gas</code> or <code>gcc</code> were configured. 125 126 <li>A description of what behavior you observe that you believe is 127incorrect. For example, “It gets a fatal signal.” 128 129 <p>Of course, if the bug is that <samp><span class="command">ld</span></samp> gets a fatal signal, then we 130will certainly notice it. But if the bug is incorrect output, we might 131not notice unless it is glaringly wrong. You might as well not give us 132a chance to make a mistake. 133 134 <p>Even if the problem you experience is a fatal signal, you should still 135say so explicitly. Suppose something strange is going on, such as, your 136copy of <samp><span class="command">ld</span></samp> is out of sync, or you have encountered a bug in the 137C library on your system. (This has happened!) Your copy might crash 138and ours would not. If you told us to expect a crash, then when ours 139fails to crash, we would know that the bug was not happening for us. If 140you had not told us to expect a crash, then we would not be able to draw 141any conclusion from our observations. 142 143 <li>If you wish to suggest changes to the <samp><span class="command">ld</span></samp> source, send us context 144diffs, as generated by <code>diff</code> with the ‘<samp><span class="samp">-u</span></samp>’, ‘<samp><span class="samp">-c</span></samp>’, or 145‘<samp><span class="samp">-p</span></samp>’ option. Always send diffs from the old file to the new file. 146If you even discuss something in the <samp><span class="command">ld</span></samp> source, refer to it by 147context, not by line number. 148 149 <p>The line numbers in our development sources will not match those in your 150sources. Your line numbers would convey no useful information to us. 151</ul> 152 153 <p>Here are some things that are not necessary: 154 155 <ul> 156<li>A description of the envelope of the bug. 157 158 <p>Often people who encounter a bug spend a lot of time investigating 159which changes to the input file will make the bug go away and which 160changes will not affect it. 161 162 <p>This is often time consuming and not very useful, because the way we 163will find the bug is by running a single example under the debugger 164with breakpoints, not by pure deduction from a series of examples. 165We recommend that you save your time for something else. 166 167 <p>Of course, if you can find a simpler example to report <em>instead</em> 168of the original one, that is a convenience for us. Errors in the 169output will be easier to spot, running under the debugger will take 170less time, and so on. 171 172 <p>However, simplification is not vital; if you do not want to do this, 173report the bug anyway and send us the entire test case you used. 174 175 <li>A patch for the bug. 176 177 <p>A patch for the bug does help us if it is a good one. But do not omit 178the necessary information, such as the test case, on the assumption that 179a patch is all we need. We might see problems with your patch and decide 180to fix the problem another way, or we might not understand it at all. 181 182 <p>Sometimes with a program as complicated as <samp><span class="command">ld</span></samp> it is very hard to 183construct an example that will make the program follow a certain path 184through the code. If you do not send us the example, we will not be 185able to construct one, so we will not be able to verify that the bug is 186fixed. 187 188 <p>And if we cannot understand what bug you are trying to fix, or why your 189patch should be an improvement, we will not install it. A test case will 190help us to understand. 191 192 <li>A guess about what the bug is or what it depends on. 193 194 <p>Such guesses are usually wrong. Even we cannot guess right about such 195things without first using the debugger to find the facts. 196</ul> 197 198 </body></html> 199 200