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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]6 <title>LLVM 1.4 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]7</head>
8<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]9
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]10<div class="doc_title">LLVM 1.4 Release Notes</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]11
12<ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]13 <li><a href="#intro">Introduction</a></li>
14 <li><a href="#whatsnew">What's New?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]15 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]16 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]17 <li><a href="#knownproblems">Known Problems</a>
18 <ul>
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]19 <li><a href="#experimental">Experimental features included in this
20 release</a>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]21 <li><a href="#core">Known problems with the LLVM Core</a>
22 <li><a href="#c-fe">Known problems with the C Front-end</a>
23 <li><a href="#c++-fe">Known problems with the C++ Front-end</a>
24 <li><a href="#x86-be">Known problems with the X86 Back-end</a>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]25 <li><a href="#sparcv9-be">Known problems with the SparcV9 Back-end</a>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]26 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]27 </ul></li>
28 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]29</ol>
30
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]31<div class="doc_author">
32 <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]33</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]34
35<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]36<div class="doc_section">
37 <a name="intro">Introduction</a>
38</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]39<!-- *********************************************************************** -->
40
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]41<div class="doc_text">
42
43<p>This document contains the release notes for the LLVM compiler
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]44infrastructure, release 1.4. Here we describe the status of LLVM, including any
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]45known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]46version of this document can be found on the <a
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]47href="http://llvm.cs.uiuc.edu/releases/1.4/">LLVM 1.4 web site</a>. If you are
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]48not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]49this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]50
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]51<p>For more information about LLVM, including information about potentially more
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]52current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main
53web site</a>. If you have questions or comments, the <a
54href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]55list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]56
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]57<p>Note that if you are reading this file from CVS, this document applies
58to the <i>next</i> release, not the current one. To see the release notes for
59the current or previous releases, see the <a
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]60href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
61
62</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]63
64<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]65<div class="doc_section">
66 <a name="whatsnew">What's New?</a>
67</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]68<!-- *********************************************************************** -->
69
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]70<div class="doc_text">
71
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]72<p>This is the fifth public release of the LLVM compiler infrastructure.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]73
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]74<p> At this time, LLVM is known to correctly compile and run all C &amp; C++
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]75SPEC CPU95 &amp; 2000 benchmarks, the Olden benchmarks, and the Ptrdist
76benchmarks, and <b>many</b> other programs. LLVM now also works
77with a broad variety of C++ programs.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]78
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]79</div>
80
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]81<!--=========================================================================-->
82<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]83<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]84</div>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]85
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]86<div class="doc_text">
87
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]88<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]89<li></li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]90</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]91
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]92</div>
93
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]94
95<!--=========================================================================-->
96<div class="doc_subsubsection">
97In this release, the following missing features were implemented:
98</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]99
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]100<div class="doc_text">
101
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]102<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]103<li><a href="http://llvm.org/PR419">JIT interface should support arbitrary
104 calls</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]105</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]106
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]107</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]108
109<!--=========================================================================-->
110<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]111<a name="qualityofimp">In this release, the following Quality of Implementation
112issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]113</div>
114
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]115<div class="doc_text">
116
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]117<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]118<li></li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]119</ol>
120
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]121</div>
122
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]123<!--=========================================================================-->
124<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]125In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]126</div>
127
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]128<div class="doc_text">
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]129<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]130<li></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]131</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]132</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]133
134<!--=========================================================================-->
135<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]136<a name="codequality">This release includes the following Code Quality
137improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]138</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]139
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]140<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]141<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]142<li></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]143</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]144</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]145
146<!--=========================================================================-->
147<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]148<a name="bugfix">In this release, the following bugs in the previous release
149were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]150</div>
151
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]152<div class="doc_text">
153
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]154<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]155
156<ol>
Chris Lattner446562f2004-08-16 05:46:57 +0000[diff] [blame^]157<li><a href="http://llvm.org/PR423">[anders-aa] Andersen's AA is completely
158 broken in LLVM 1.3</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]159</ol>
160
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]161<p>Bugs in the C/C++ front-end:</p>
162
163<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]164<li></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]165</ol>
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
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]176<p>LLVM is known to work in the following platforms:</p>
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 Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]182<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnere58d3562004-08-05 21:53:13 +0000[diff] [blame]183<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
184support is available yet, and LLC support is beta. The C backend can be used
185to produce stable code for this platform.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]186</ul>
187
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]188<p>The core LLVM infrastructure uses
189<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
190to the machine and operating system on which it is built. However, minor
191porting may be required to get LLVM to work on new platforms. We welcome your
192portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]193
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]194<p>Note that the LLVM build system does not currently support directories with
195spaces on them when running on Win32/cygwin. We strongly recommend running
196LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]197<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
198cygwin packages. By default, many important tools are not installed that
199are needed by the LLVM build process or test suite (e.g., /bin/time).</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]200
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]201</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]202
203<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]204<div class="doc_section">
205 <a name="knownproblems">Known Problems</a>
206</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]207<!-- *********************************************************************** -->
208
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]209<div class="doc_text">
210
211<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]212component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]213sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]214href="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]215there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]216
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]217</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]218
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]219<!-- ======================================================================= -->
220<div class="doc_subsection">
221 <a name="experimental">Experimental features included with this release</a>
222</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]223
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]224<div class="doc_text">
225
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]226<p>The following components of this LLVM release are either untested, known to
227be broken or unreliable, or are in early development. These components should
228not be relied on, and bugs should not be filed against them, but they may be
229useful to some people. In particular, if you would like to work on one of these
230components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]231
232<ul>
Misha Brukman94118752004-08-05 21:04:03 +0000[diff] [blame]233<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
234benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
235details.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]236<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattnercbabe702004-06-28 00:44:45 +0000[diff] [blame]237 -ipmodref, -cee</tt></li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]238<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
239 it should) and not thoroughly tested.</li>
240<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
241<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
242</ul>
243
244</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]245
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]246<!-- ======================================================================= -->
247<div class="doc_subsection">
248 <a name="core">Known problems with the LLVM Core</a>
249</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]250
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]251<div class="doc_text">
252
253<ul>
254
255<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
256work.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]257
258<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]259such, execution of a threaded program could cause these data structures to be
260corrupted.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]261
Chris Lattnereb673962004-08-08 03:33:07 +0000[diff] [blame]262<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]263table in the archive).</li>
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]264
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]265<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
266objects/archives in the order specified on the command line.</a></li>
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]267
268<li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not mark
John Criswelld46c6962004-03-12 21:29:42 +0000[diff] [blame]269values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]270targets whose setjmp/longjmp libraries do not save and restore the entire
271register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]272</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]273</div>
274
275<!-- ======================================================================= -->
276<div class="doc_subsection">
277 <a name="c-fe">Known problems with the C front-end</a>
278</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]279
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]280<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]281<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]282
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]283<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]284<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]285<li>C99 Variable sized arrays do not release stack memory when they go out of
286 scope. Thus, the following program may run out of stack space:
287<pre>
288 for (i = 0; i != 1000000; ++i) {
289 int X[n];
290 foo(X);
291 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]292</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]293
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]294<li>Initialization of global union variables can only be done <a
295href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
296member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]297
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]298<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
299external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]300
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]301</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]302</div>
303
304<!-- _______________________________________________________________________ -->
305<div class="doc_subsubsection">
306 Notes
307</div>
308
309<div class="doc_text">
310
311<ul>
312
313<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]314
315<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]316support for floating point data types of any size other than 32 and 64
317bits.</li>
318
319<li>The following Unix system functionality has not been tested and may not
320work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]321 <ol>
322 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
323 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
324 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
325 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
326 - These functions have not been tested.
327 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]328
329<li>Although many GCC extensions are supported, some are not. In particular,
330 the following extensions are known to <b>not be</b> supported:
331 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]332 <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]333 <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>
334 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
335 <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]336 <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]337 <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>
338 <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]339 <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>
340 <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>
341 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
342 <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]343 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]344
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]345 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]346 attribute means that the LLVM compiler ignores the presence of the attribute,
347 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]348 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]349 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]350
351 <ol>
352 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
353 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]354 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]355
356 <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]357
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]358 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]359 return.<br>
360
361 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
362 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
363 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
364
365 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
366 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
367 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
368
369 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
370 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
371 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]372
373 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
374 Specifying attributes of variables.<br>
375 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
376 <tt>deprecated</tt>, <tt>transparent_union</tt>,
377 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]378
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]379 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
380 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
381 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]382 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]383
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]384 <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]385 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]386 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]387
388 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
389 all target specific attributes.</li>
390
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]391 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
392 Other built-in functions.<br>
393 We support all builtins which have a C language equivalent (e.g.,
394 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
395 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]396 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
397 (currently ignored). We also support builtins for ISO C99 floating
398 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]399 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]400
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]401 <p>The following extensions <b>are</b> known to be supported:</p>
402
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]403 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]404 <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]405 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
406 <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]407 <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]408 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
409 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
410 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
411 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
412 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
413 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
414 <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>
415 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
416 <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]417 <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]418 <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]419 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
420or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]421 <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]422 <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]423 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
424 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
425 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
426 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
427 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
428 <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>
429 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
430 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
431 <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>
432 <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>
433 <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]434 <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]435 <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>
436 <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]437 </ol></li>
438
439</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]440
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]441<p>If you run into GCC extensions which have not been included in any of these
442lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]443
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]444</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]445
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]446<!-- ======================================================================= -->
447<div class="doc_subsection">
448 <a name="c++-fe">Known problems with the C++ front-end</a>
449</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]450
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]451<div class="doc_text">
452
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]453<p>For this release, the C++ front-end is considered to be fully functional but
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]454has not been tested as thoroughly as the C front-end. It has been tested and
455works for a number of non-trivial programs, but there may be lurking bugs.
456Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]457
458</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]459
460<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]461<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]462
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]463<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]464
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]465<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]466<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]467 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]468
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]469<li><b>IA-64 specific</b>: The C++ front-end does not use <a
470href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]471In particular, it just stores function pointers instead of function
472descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]473LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]474
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]475</ul>
476
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]477</div>
478
479<!-- _______________________________________________________________________ -->
480<div class="doc_subsubsection">
481 Notes
482</div>
483
484<div class="doc_text">
485
486<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]487
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]488<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
489parser is significantly more standards compliant (and picky) than prior GCC
490versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]491href="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]492
493<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]494 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]495 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]496 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]497 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]498
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]499<li>The LLVM C++ front-end follows the <a
500 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
501 This document, which is not Itanium specific, specifies a standard for name
502 mangling, class layout, v-table layout, RTTI formats, and other C++
503 representation issues. Because we use this API, code generated by the LLVM
504 compilers should be binary compatible with machine code generated by other
505 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
506 <i>However</i>, the exception handling mechanism used by LLVM is very
507 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]508 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]509
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]510</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]511
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]512</div>
513
514<!-- ======================================================================= -->
515<div class="doc_subsection">
516 <a name="x86-be">Known problems with the X86 back-end</a>
517</div>
518
519<div class="doc_text">
520
521<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]522 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]523</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]524
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]525</div>
526
527<!-- ======================================================================= -->
528<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]529 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]530</div>
531
532<div class="doc_text">
533
534<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]535<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
536several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]537</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]538
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]539</div>
540
541<!-- ======================================================================= -->
542<div class="doc_subsection">
543 <a name="c-be">Known problems with the C back-end</a>
544</div>
545
546<div class="doc_text">
547
548<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]549
550<li>The C back-end produces code that violates the ANSI C Type-Based Alias
551Analysis rules. As such, special options may be necessary to compile the code
552(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]553problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]554
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]555<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]556cannot include special floating point numbers like Not-A-Number or
557Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]558
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]559<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]560supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]561frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]562
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]563</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]564
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]565</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]566
567<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]568<div class="doc_section">
569 <a name="additionalinfo">Additional Information</a>
570</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]571<!-- *********************************************************************** -->
572
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]573<div class="doc_text">
574
575<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]576including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]577implemented in LLVM. The web page also contains versions of the API
578documentation which is up-to-date with the CVS version of the source code. You
579can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]580the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]581
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]582<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]583us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
584lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]585
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]586</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]587
588<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]589
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]590<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]591<address>
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596
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]597 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]598 Last modified: $Date$
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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]601</body>
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