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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / f54e9cb739dfba8b39549c09fc5a1e367ca13be3 / . / docs / ReleaseNotes.html
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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2 "http://www.w3.org/TR/html4/strict.dtd">
3<html>
4<head>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]6 <link rel="stylesheet" href="llvm.css" type="text/css">
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]7 <title>LLVM 1.5 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]10
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]11<div class="doc_title">LLVM 1.5 Release Notes</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]12
13<ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]14 <li><a href="#intro">Introduction</a></li>
15 <li><a href="#whatsnew">What's New?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]16 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]18 <li><a href="#knownproblems">Known Problems</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]19 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]20</ol>
21
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]22<div class="doc_author">
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]23 <p>Written by the <a href="http://llvm.cs.uiuc.edu">LLVM Team</a><p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]24</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]25
26<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]27<div class="doc_section">
28 <a name="intro">Introduction</a>
29</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]30<!-- *********************************************************************** -->
31
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]32<div class="doc_text">
33
34<p>This document contains the release notes for the LLVM compiler
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]35infrastructure, release 1.5. Here we describe the status of LLVM, including any
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]36known problems and improvements from the previous release. The most up-to-date
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]37version of this document can be found on the <a
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]38href="http://llvm.cs.uiuc.edu/releases/1.5/">LLVM 1.5 web site</a>. If you are
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]39not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]40this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]41
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]42<p>For more information about LLVM, including information about the latest
43release, please check out the <a href="http://llvm.cs.uiuc.edu">main LLVM
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]44web site</a>. If you have questions or comments, the <a
45href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]46list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]47
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]48<p>Note that if you are reading this file from CVS or the main LLVM web page,
49this document applies to the <i>next</i> release, not the current one. To see
50the release notes for the current or previous releases, see the <a
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]51href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
52
53</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]54
55<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]56<div class="doc_section">
57 <a name="whatsnew">What's New?</a>
58</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]59<!-- *********************************************************************** -->
60
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]61<div class="doc_text">
62
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]63<p>This is the sixth public release of the LLVM compiler infrastructure.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]64
Chris Lattner0bce6ac2004-12-10 16:27:34 +0000[diff] [blame]65<p> At this time, LLVM is known to correctly compile a broad range of C and
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]66C++ programs, including the SPEC CPU95 &amp; 2000 suite. TODO. It also includes
67bug fixes for those problems found since the 1.4 release.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]68
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]69</div>
70
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]71<!--=========================================================================-->
72<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]73<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]74</div>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]75
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]76<div class="doc_text">
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]77<ol>
Chris Lattner74d74cd2004-12-11 06:10:52 +0000[diff] [blame]78 <li>LLVM now includes an <a href="http://llvm.cs.uiuc.edu/PR415">
Chris Lattnerda1f03c2005-01-22 18:45:35 +0000[diff] [blame]79 Interprocedural Sparse Conditional Constant Propagation</a> pass, named
Chris Lattner74d74cd2004-12-11 06:10:52 +0000[diff] [blame]80 -ipsccp, which is run by default at link-time.</li>
Chris Lattner75008d82005-02-01 01:33:52 +0000[diff] [blame]81 <li>LLVM 1.5 is now about 15% faster than LLVM 1.4 and its core data structures
Chris Lattner2e12c742005-02-13 22:27:24 +0000[diff] [blame]82 use about 30% less memory.</li>
83 <li>LLVM includes new experimental native code generators for SparcV8 and
84 Alpha.</li>
85 <li>Support for Microsoft Visual Studio is improved, and <a
86 href="GettingStartedVS.html">not documented</a>.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]87</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]88
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]89</div>
90
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]91
92<!--=========================================================================-->
93<div class="doc_subsubsection">
94In this release, the following missing features were implemented:
95</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]96
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]97<div class="doc_text">
98
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]99<ol>
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]100 <li></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]101</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]102
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]103</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]104
105<!--=========================================================================-->
106<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]107<a name="qualityofimp">In this release, the following Quality of Implementation
108issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]109</div>
110
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]111<div class="doc_text">
112
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]113<ol>
Chris Lattnerda1f03c2005-01-22 18:45:35 +0000[diff] [blame]114 <li><a href="http://llvm.cs.uiuc.edu/PR448">Building LLVM in optimized mode
115 should no longer cause GCC to hit swap in the PowerPC backend.</a></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]116</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]117</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]118
119<!--=========================================================================-->
120<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]121<a name="codequality">This release includes the following Code Quality
122improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]123</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]124
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]125<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]126<ol>
Chris Lattner78bf32b2004-12-09 22:22:58 +0000[diff] [blame]127 <li></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]128</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]129</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]130
131<!--=========================================================================-->
132<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]133<a name="bugfix">In this release, the following bugs in the previous release
134were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]135</div>
136
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]137<div class="doc_text">
138
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]139
Chris Lattnerf54e9cb2005-02-14 16:57:55 +0000[diff] [blame^]140<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]141<ol>
Chris Lattnerbfd24682004-12-29 04:39:50 +0000[diff] [blame]142 <li><a href="http://llvm.cs.uiuc.edu/PR491">[dse] DSE deletes stores that
143 are partially overwritten by smaller stores</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]144</ol>
145
Chris Lattnerf54e9cb2005-02-14 16:57:55 +0000[diff] [blame^]146<p>Code Generator Bugs:</p>
147<ol>
148 <li><a href="http://llvm.cs.uiuc.edu/PR490">[cbackend] Logical constant
149 expressions (and/or/xor) not implemented</a></li>
150 <li><a href="http://llvm.cs.uiuc.edu/PR511">[cbackend] C backend does not
151 respect 'volatile'</a></li>
152</ol>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]153
Chris Lattnerf54e9cb2005-02-14 16:57:55 +0000[diff] [blame^]154<p>Bugs in the C/C++ front-end:</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]155<ol>
Chris Lattner8de9f232005-01-03 04:20:21 +0000[diff] [blame]156 <li><a href="http://llvm.cs.uiuc.edu/PR487">[llvmgcc] llvm-gcc incorrectly
157 rejects some constant initializers involving the addresses of array
158 elements</a></li>
Chris Lattnerf832f6a2005-02-11 19:29:52 +0000[diff] [blame]159 <li><a href="http://llvm.cs.uiuc.edu/PR501">[llvm-g++] Crash compiling
160 anonymous union</a></li>
Chris Lattnerf54e9cb2005-02-14 16:57:55 +0000[diff] [blame^]161 <li><a href="http://llvm.cs.uiuc.edu/PR509">[llvm-g++] Do not use dynamic
162 initialization where static init will do</a></li>
163 <li>
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]164</ol>
165
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]166</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]167
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]168<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]169<div class="doc_section">
170 <a name="portability">Portability and Supported Platforms</a>
171</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]172<!-- *********************************************************************** -->
173
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]174<div class="doc_text">
175
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]176<p>LLVM is known to work on the following platforms:</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]177
178<ul>
179<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
180 other unix-like systems).</li>
181<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]182<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
183 support is available for native builds with Visual C++).</li>
184<li>PowerPC-based Mac OS X systems, running 10.2 and above.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]185</ul>
186
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]187<p>The core LLVM infrastructure uses
188<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
189to the machine and operating system on which it is built. However, minor
190porting may be required to get LLVM to work on new platforms. We welcome your
191portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]192
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]193</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]194
195<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]196<div class="doc_section">
197 <a name="knownproblems">Known Problems</a>
198</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]199<!-- *********************************************************************** -->
200
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]201<div class="doc_text">
202
203<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]204component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]205sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]206href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]207there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]208
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]209</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]210
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]211<!-- ======================================================================= -->
212<div class="doc_subsection">
213 <a name="experimental">Experimental features included with this release</a>
214</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]215
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]216<div class="doc_text">
217
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]218<p>The following components of this LLVM release are either untested, known to
219be broken or unreliable, or are in early development. These components should
220not be relied on, and bugs should not be filed against them, but they may be
221useful to some people. In particular, if you would like to work on one of these
222components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]223
224<ul>
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]225<li>The following passes are incomplete or buggy, and may be removed in future
Chris Lattner1fe848e2005-01-28 06:13:52 +0000[diff] [blame]226 releases: <tt>-cee, -branch-combine, -instloops, -paths, -pre</tt></li>
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]227<li>The <tt>llvm-db</tt> tool is in a very early stage of development, but can
228 be used to step through programs and inspect the stack.</li>
Chris Lattner0da7f492004-12-02 17:20:17 +0000[diff] [blame]229<li>The "iterative scan" register allocator (enabled with -regalloc=iterativescan)
230 is not stable.</li>
Chris Lattner2e12c742005-02-13 22:27:24 +0000[diff] [blame]231<li>The SparcV8 and Alpha ports are experimental.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]232</ul>
233
234</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]235
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]236<!-- ======================================================================= -->
237<div class="doc_subsection">
238 <a name="core">Known problems with the LLVM Core</a>
239</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]240
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]241<div class="doc_text">
242
243<ul>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]244 <li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not work.
245 </li>
246 <li>The JIT does not use mutexes to protect its internal data structures. As
247 such, execution of a threaded program could cause these data structures to be
248 corrupted.
249 </li>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]250 <li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not
251 mark values live across a setjmp as volatile</a>. This missing feature
252 only affects targets whose setjmp/longjmp libraries do not save and restore
253 the entire register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]254</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]255</div>
256
257<!-- ======================================================================= -->
258<div class="doc_subsection">
259 <a name="c-fe">Known problems with the C front-end</a>
260</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]261
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]262<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]263<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]264
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]265<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]266<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]267<li>C99 Variable sized arrays do not release stack memory when they go out of
268 scope. Thus, the following program may run out of stack space:
269<pre>
270 for (i = 0; i != 1000000; ++i) {
271 int X[n];
272 foo(X);
273 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]274</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]275
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]276<li>Initialization of global union variables can only be done <a
Misha Brukman43ee2932004-12-04 00:45:09 +0000[diff] [blame]277href="http://llvm.cs.uiuc.edu/PR162">with the largest union member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]278
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]279</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]280</div>
281
282<!-- _______________________________________________________________________ -->
283<div class="doc_subsubsection">
284 Notes
285</div>
286
287<div class="doc_text">
288
289<ul>
290
291<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]292
293<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]294support for floating point data types of any size other than 32 and 64
295bits.</li>
296
297<li>The following Unix system functionality has not been tested and may not
298work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]299 <ol>
300 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
301 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
302 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
303 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
304 - These functions have not been tested.
305 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]306
307<li>Although many GCC extensions are supported, some are not. In particular,
308 the following extensions are known to <b>not be</b> supported:
309 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]310 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]311 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Nested-Functions.html#Nested%20Functions">Nested Functions</a>: As in Algol and Pascal, lexical scoping of functions.</li>
312 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
313 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Extended%20Asm">Extended Asm</a>: Assembler instructions with C expressions as operands.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]314 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]315 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Asm-Labels.html#Asm%20Labels">Asm Labels</a>: Specifying the assembler name to use for a C symbol.</li>
316 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Explicit-Reg-Vars.html#Explicit%20Reg%20Vars">Explicit Reg Vars</a>: Defining variables residing in specified registers.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]317 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Vector-Extensions.html#Vector%20Extensions">Vector Extensions</a>: Using vector instructions through built-in functions.</li>
318 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Target-Builtins.html#Target%20Builtins">Target Builtins</a>: Built-in functions specific to particular targets.</li>
Tanya Lattner014e5f52004-12-08 18:25:34 +0000[diff] [blame]319 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread_002dLocal.html">Thread-Local</a>: Per-thread variables.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]320 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li>
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]321 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]322
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]323 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]324 attribute means that the LLVM compiler ignores the presence of the attribute,
325 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]326 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]327 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]328
329 <ol>
330 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
331 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]332 Supported, but allocated stack space is not freed until the function returns (noted above).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]333
334 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>:
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]335
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]336 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]337 return.<br>
338
339 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]340 <tt>noreturn</tt>, <tt>constructor</tt>, <tt>destructor</tt>,
341 <tt>unused</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]342 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
343
John Criswell0b5b5e92004-12-08 20:35:47 +0000[diff] [blame]344 <b>Ignored:</b> <tt>noinline</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]345 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
346 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
347
348 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
349 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
350 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]351
352 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
353 Specifying attributes of variables.<br>
354 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
355 <tt>deprecated</tt>, <tt>transparent_union</tt>,
356 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]357
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]358 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
359 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
360 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]361 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]362
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]363 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.<br>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]364 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]365 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]366
367 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
368 all target specific attributes.</li>
369
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]370 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
371 Other built-in functions.<br>
372 We support all builtins which have a C language equivalent (e.g.,
373 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
374 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]375 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
376 (currently ignored). We also support builtins for ISO C99 floating
377 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]378 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]379
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]380 <p>The following extensions <b>are</b> known to be supported:</p>
381
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]382 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]383 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html#Labels%20as%20Values">Labels as Values</a>: Getting pointers to labels and computed gotos.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]384 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
385 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Typeof.html#Typeof">Typeof</a>: <code>typeof</code>: referring to the type of an expression.</li>
Tanya Lattnerca26c3e2004-06-22 03:48:17 +0000[diff] [blame]386 <li><a href="http://gcc.gnu.org/onlinedocs/gcc-3.4.0/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]387 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
388 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
389 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
390 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
391 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
392 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
393 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variadic-Macros.html#Variadic%20Macros">Variadic Macros</a>: Macros with a variable number of arguments.</li>
394 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
395 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Subscripting.html#Subscripting">Subscripting</a>: Any array can be subscripted, even if not an lvalue.</li>
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]396 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pointer-Arith.html#Pointer%20Arith">Pointer Arith</a>: Arithmetic on <code>void</code>-pointers and function pointers.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]397 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]398 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
399or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]400 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]401 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Cast-to-Union.html#Cast%20to%20Union">Cast to Union</a>: Casting to union type from any member of the union.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]402 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
403 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
404 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
Tanya Lattner78537e42004-12-08 18:29:38 +0000[diff] [blame]405 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Comments.html#C_002b_002b-Comments">C++ Comments</a>: C++ comments are recognized.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]406 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
407 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Character-Escapes.html#Character%20Escapes">Character Escapes</a>: <code>\e</code> stands for the character &lt;ESC&gt;.</li>
408 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
409 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
410 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alternate-Keywords.html#Alternate%20Keywords">Alternate Keywords</a>:<code>__const__</code>, <code>__asm__</code>, etc., for header files.</li>
411 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Incomplete-Enums.html#Incomplete%20Enums">Incomplete Enums</a>: <code>enum foo;</code>, with details to follow.</li>
412 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Names.html#Function%20Names">Function Names</a>: Printable strings which are the name of the current function.</li>
Chris Lattner25795bc2004-02-14 04:08:29 +0000[diff] [blame]413 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Return-Address.html#Return%20Address">Return Address</a>: Getting the return or frame address of a function.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]414 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Unnamed-Fields.html#Unnamed%20Fields">Unnamed Fields</a>: Unnamed struct/union fields within structs/unions.</li>
415 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute%20Syntax">Attribute Syntax</a>: Formal syntax for attributes.</li>
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]416 </ol></li>
417
418</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]419
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]420<p>If you run into GCC extensions which have not been included in any of these
421lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]422
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]423</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]424
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]425<!-- ======================================================================= -->
426<div class="doc_subsection">
427 <a name="c++-fe">Known problems with the C++ front-end</a>
428</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]429
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]430<div class="doc_text">
431
Reid Spencere09ca642004-12-07 08:39:08 +0000[diff] [blame]432<p>For this release, the C++ front-end is considered to be fully
Chris Lattner7506b1d2004-12-07 08:04:13 +0000[diff] [blame]433tested and works for a number of non-trivial programs, including LLVM
434itself.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]435
436</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]437
438<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]439<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]440
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]441<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]442
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]443<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]444<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]445 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]446
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]447<li><b>IA-64 specific</b>: The C++ front-end does not use <a
448href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]449In particular, it just stores function pointers instead of function
450descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]451LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]452
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]453</ul>
454
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]455</div>
456
457<!-- _______________________________________________________________________ -->
458<div class="doc_subsubsection">
459 Notes
460</div>
461
462<div class="doc_text">
463
464<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]465
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]466<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
467parser is significantly more standards compliant (and picky) than prior GCC
468versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]469href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]470
471<li>Destructors for local objects are not always run when a <tt>longjmp</tt> is
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]472 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]473 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]474 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]475 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]476
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]477<li>The LLVM C++ front-end follows the <a
478 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
479 This document, which is not Itanium specific, specifies a standard for name
480 mangling, class layout, v-table layout, RTTI formats, and other C++
481 representation issues. Because we use this API, code generated by the LLVM
482 compilers should be binary compatible with machine code generated by other
483 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
484 <i>However</i>, the exception handling mechanism used by LLVM is very
485 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]486 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]487
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]488</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]489
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]490</div>
491
492<!-- ======================================================================= -->
493<div class="doc_subsection">
494 <a name="x86-be">Known problems with the X86 back-end</a>
495</div>
496
497<div class="doc_text">
498
499<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]500 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]501</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]502
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]503</div>
504
505<!-- ======================================================================= -->
506<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]507 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]508</div>
509
510<div class="doc_text">
511
512<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]513<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
514several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]515</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]516
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]517</div>
518
519<!-- ======================================================================= -->
520<div class="doc_subsection">
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]521 <a name="ppc-be">Known problems with the PowerPC back-end</a>
522</div>
523
524<div class="doc_text">
525
526<ul>
527<li>none yet</li>
528</ul>
529
530</div>
531
532<!-- ======================================================================= -->
533<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]534 <a name="c-be">Known problems with the C back-end</a>
535</div>
536
537<div class="doc_text">
538
539<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]540
541<li>The C back-end produces code that violates the ANSI C Type-Based Alias
542Analysis rules. As such, special options may be necessary to compile the code
543(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]544problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]545
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]546<li><a href="http://llvm.cs.uiuc.edu/PR56">Zero arg vararg functions are not
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]547supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]548frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]549
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]550</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]551
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]552</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]553
554<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]555<div class="doc_section">
556 <a name="additionalinfo">Additional Information</a>
557</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]558<!-- *********************************************************************** -->
559
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]560<div class="doc_text">
561
562<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]563including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]564implemented in LLVM. The web page also contains versions of the API
565documentation which is up-to-date with the CVS version of the source code. You
566can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]567the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]568
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]569<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]570us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
571lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]572
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]573</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]574
575<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]576
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]577<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]578<address>
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583
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]584 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]585 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]586</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]587
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]588</body>
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