1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- Copyright (C) 1988-2021 Free Software Foundation, Inc. 4 5Permission is granted to copy, distribute and/or modify this document 6under the terms of the GNU Free Documentation License, Version 1.3 or 7any later version published by the Free Software Foundation; with the 8Invariant Sections being "Free Software" and "Free Software Needs 9Free Documentation", with the Front-Cover Texts being "A GNU Manual," 10and with the Back-Cover Texts as in (a) below. 11 12(a) The FSF's Back-Cover Text is: "You are free to copy and modify 13this GNU Manual. 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They have 75the generalized form *<var>address</var>. 76</p> 77<p>For line-oriented commands, such as <code>list</code> and <code>edit</code>, this 78specifies a source line that contains <var>address</var>. For <code>break</code> and 79other breakpoint-oriented commands, this can be used to set breakpoints in 80parts of your program which do not have debugging information or 81source files. 82</p> 83<p>Here <var>address</var> may be any expression valid in the current working 84language (see <a href="Languages.html#Languages">working language</a>) that specifies a code 85address. In addition, as a convenience, <small>GDB</small> extends the 86semantics of expressions used in locations to cover several situations 87that frequently occur during debugging. Here are the various forms 88of <var>address</var>: 89</p> 90<dl compact="compact"> 91<dt><code><var>expression</var></code></dt> 92<dd><p>Any expression valid in the current working language. 93</p> 94</dd> 95<dt><code><var>funcaddr</var></code></dt> 96<dd><p>An address of a function or procedure derived from its name. In C, 97C<tt>++</tt>, Objective-C, Fortran, minimal, and assembly, this is 98simply the function’s name <var>function</var> (and actually a special case 99of a valid expression). In Pascal and Modula-2, this is 100<code>&<var>function</var></code>. In Ada, this is <code><var>function</var>'Address</code> 101(although the Pascal form also works). 102</p> 103<p>This form specifies the address of the function’s first instruction, 104before the stack frame and arguments have been set up. 105</p> 106</dd> 107<dt><code>'<var>filename</var>':<var>funcaddr</var></code></dt> 108<dd><p>Like <var>funcaddr</var> above, but also specifies the name of the source 109file explicitly. This is useful if the name of the function does not 110specify the function unambiguously, e.g., if there are several 111functions with identical names in different source files. 112</p></dd> 113</dl> 114 115 116 117 118</body> 119</html> 120