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diff --git a/share/doc/gdb/Inline-Functions.html b/share/doc/gdb/Inline-Functions.html new file mode 100644 index 0000000..fc0eb29 --- /dev/null +++ b/share/doc/gdb/Inline-Functions.html @@ -0,0 +1,134 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<html> +<!-- Copyright (C) 1988-2023 Free Software Foundation, Inc. + +Permission is granted to copy, distribute and/or modify this document +under the terms of the GNU Free Documentation License, Version 1.3 or +any later version published by the Free Software Foundation; with the +Invariant Sections being "Free Software" and "Free Software Needs +Free Documentation", with the Front-Cover Texts being "A GNU Manual," +and with the Back-Cover Texts as in (a) below. + +(a) The FSF's Back-Cover Text is: "You are free to copy and modify +this GNU Manual. Buying copies from GNU Press supports the FSF in +developing GNU and promoting software freedom." --> +<!-- Created by GNU Texinfo 5.1, http://www.gnu.org/software/texinfo/ --> +<head> +<title>Debugging with GDB: Inline Functions</title> + +<meta name="description" content="Debugging with GDB: Inline Functions"> +<meta name="keywords" content="Debugging with GDB: Inline Functions"> +<meta name="resource-type" content="document"> +<meta name="distribution" content="global"> +<meta name="Generator" content="makeinfo"> +<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> +<link href="index.html#Top" rel="start" title="Top"> +<link href="Concept-Index.html#Concept-Index" rel="index" title="Concept Index"> +<link href="index.html#SEC_Contents" rel="contents" title="Table of Contents"> +<link href="Optimized-Code.html#Optimized-Code" rel="up" title="Optimized Code"> +<link href="Tail-Call-Frames.html#Tail-Call-Frames" rel="next" title="Tail Call Frames"> +<link href="Optimized-Code.html#Optimized-Code" rel="previous" title="Optimized Code"> +<style type="text/css"> +<!-- +a.summary-letter {text-decoration: none} +blockquote.smallquotation {font-size: smaller} +div.display {margin-left: 3.2em} +div.example {margin-left: 3.2em} +div.indentedblock {margin-left: 3.2em} +div.lisp {margin-left: 3.2em} +div.smalldisplay {margin-left: 3.2em} +div.smallexample {margin-left: 3.2em} +div.smallindentedblock {margin-left: 3.2em; font-size: smaller} +div.smalllisp {margin-left: 3.2em} +kbd {font-style:oblique} +pre.display {font-family: inherit} +pre.format {font-family: inherit} +pre.menu-comment {font-family: serif} +pre.menu-preformatted {font-family: serif} +pre.smalldisplay {font-family: inherit; font-size: smaller} +pre.smallexample {font-size: smaller} +pre.smallformat {font-family: inherit; font-size: smaller} +pre.smalllisp {font-size: smaller} +span.nocodebreak {white-space:nowrap} +span.nolinebreak {white-space:nowrap} +span.roman {font-family:serif; font-weight:normal} +span.sansserif {font-family:sans-serif; font-weight:normal} +ul.no-bullet {list-style: none} +--> +</style> + + +</head> + +<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000"> +<a name="Inline-Functions"></a> +<div class="header"> +<p> +Next: <a href="Tail-Call-Frames.html#Tail-Call-Frames" accesskey="n" rel="next">Tail Call Frames</a>, Up: <a href="Optimized-Code.html#Optimized-Code" accesskey="u" rel="up">Optimized Code</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> +<hr> +<a name="Inline-Functions-1"></a> +<h3 class="section">11.1 Inline Functions</h3> +<a name="index-inline-functions_002c-debugging"></a> + +<p><em>Inlining</em> is an optimization that inserts a copy of the function +body directly at each call site, instead of jumping to a shared +routine. <small>GDB</small> displays inlined functions just like +non-inlined functions. They appear in backtraces. You can view their +arguments and local variables, step into them with <code>step</code>, skip +them with <code>next</code>, and escape from them with <code>finish</code>. +You can check whether a function was inlined by using the +<code>info frame</code> command. +</p> +<p>For <small>GDB</small> to support inlined functions, the compiler must +record information about inlining in the debug information — +<small>GCC</small> using the <small>DWARF 2</small> format does this, and several +other compilers do also. <small>GDB</small> only supports inlined functions +when using <small>DWARF 2</small>. Versions of <small>GCC</small> before 4.1 +do not emit two required attributes (‘<samp>DW_AT_call_file</samp>’ and +‘<samp>DW_AT_call_line</samp>’); <small>GDB</small> does not display inlined +function calls with earlier versions of <small>GCC</small>. It instead +displays the arguments and local variables of inlined functions as +local variables in the caller. +</p> +<p>The body of an inlined function is directly included at its call site; +unlike a non-inlined function, there are no instructions devoted to +the call. <small>GDB</small> still pretends that the call site and the +start of the inlined function are different instructions. Stepping to +the call site shows the call site, and then stepping again shows +the first line of the inlined function, even though no additional +instructions are executed. +</p> +<p>This makes source-level debugging much clearer; you can see both the +context of the call and then the effect of the call. Only stepping by +a single instruction using <code>stepi</code> or <code>nexti</code> does not do +this; single instruction steps always show the inlined body. +</p> +<p>There are some ways that <small>GDB</small> does not pretend that inlined +function calls are the same as normal calls: +</p> +<ul> +<li> Setting breakpoints at the call site of an inlined function may not +work, because the call site does not contain any code. <small>GDB</small> +may incorrectly move the breakpoint to the next line of the enclosing +function, after the call. This limitation will be removed in a future +version of <small>GDB</small>; until then, set a breakpoint on an earlier line +or inside the inlined function instead. + +</li><li> <small>GDB</small> cannot locate the return value of inlined calls after +using the <code>finish</code> command. This is a limitation of compiler-generated +debugging information; after <code>finish</code>, you can step to the next line +and print a variable where your program stored the return value. + +</li></ul> + +<hr> +<div class="header"> +<p> +Next: <a href="Tail-Call-Frames.html#Tail-Call-Frames" accesskey="n" rel="next">Tail Call Frames</a>, Up: <a href="Optimized-Code.html#Optimized-Code" accesskey="u" rel="up">Optimized Code</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Concept-Index.html#Concept-Index" title="Index" rel="index">Index</a>]</p> +</div> + + + +</body> +</html> |