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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>
Reid Spencer51d1cb32004-08-16 16:48:19 +0000[diff] [blame]157<li><a href="http://llvm.org/PR422">[asmwriter] Asmwriter is really slow for
158 functions with lots of values</a></li>
Chris Lattner446562f2004-08-16 05:46:57 +0000[diff] [blame]159<li><a href="http://llvm.org/PR423">[anders-aa] Andersen's AA is completely
160 broken in LLVM 1.3</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]161</ol>
162
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]163<p>Bugs in the C/C++ front-end:</p>
164
165<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]166<li></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]167</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]168</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]169
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]170<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]171<div class="doc_section">
172 <a name="portability">Portability and Supported Platforms</a>
173</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]174<!-- *********************************************************************** -->
175
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]176<div class="doc_text">
177
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]178<p>LLVM is known to work in the following platforms:</p>
179
180<ul>
181<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
182 other unix-like systems).</li>
183<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]184<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnere58d3562004-08-05 21:53:13 +0000[diff] [blame]185<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
186support is available yet, and LLC support is beta. The C backend can be used
187to produce stable code for this platform.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]188</ul>
189
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]190<p>The core LLVM infrastructure uses
191<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
192to the machine and operating system on which it is built. However, minor
193porting may be required to get LLVM to work on new platforms. We welcome your
194portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]195
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]196<p>Note that the LLVM build system does not currently support directories with
197spaces on them when running on Win32/cygwin. We strongly recommend running
198LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]199<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
200cygwin packages. By default, many important tools are not installed that
201are needed by the LLVM build process or test suite (e.g., /bin/time).</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]202
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]203</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]204
205<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]206<div class="doc_section">
207 <a name="knownproblems">Known Problems</a>
208</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]209<!-- *********************************************************************** -->
210
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]211<div class="doc_text">
212
213<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]214component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]215sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]216href="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]217there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]218
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]219</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]220
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]221<!-- ======================================================================= -->
222<div class="doc_subsection">
223 <a name="experimental">Experimental features included with this release</a>
224</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]225
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]226<div class="doc_text">
227
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]228<p>The following components of this LLVM release are either untested, known to
229be broken or unreliable, or are in early development. These components should
230not be relied on, and bugs should not be filed against them, but they may be
231useful to some people. In particular, if you would like to work on one of these
232components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]233
234<ul>
Misha Brukman94118752004-08-05 21:04:03 +0000[diff] [blame]235<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
236benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
237details.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]238<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattnercbabe702004-06-28 00:44:45 +0000[diff] [blame]239 -ipmodref, -cee</tt></li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]240<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
241 it should) and not thoroughly tested.</li>
242<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
243<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
244</ul>
245
246</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]247
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]248<!-- ======================================================================= -->
249<div class="doc_subsection">
250 <a name="core">Known problems with the LLVM Core</a>
251</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]252
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]253<div class="doc_text">
254
255<ul>
256
257<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
258work.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]259
260<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]261such, execution of a threaded program could cause these data structures to be
262corrupted.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]263
Chris Lattnereb673962004-08-08 03:33:07 +0000[diff] [blame]264<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]265table in the archive).</li>
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]266
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]267<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
268objects/archives in the order specified on the command line.</a></li>
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]269
270<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]271values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]272targets whose setjmp/longjmp libraries do not save and restore the entire
273register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]274</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]275</div>
276
277<!-- ======================================================================= -->
278<div class="doc_subsection">
279 <a name="c-fe">Known problems with the C front-end</a>
280</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]281
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]282<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]283<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]284
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]285<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]286<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]287<li>C99 Variable sized arrays do not release stack memory when they go out of
288 scope. Thus, the following program may run out of stack space:
289<pre>
290 for (i = 0; i != 1000000; ++i) {
291 int X[n];
292 foo(X);
293 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]294</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]295
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]296<li>Initialization of global union variables can only be done <a
297href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
298member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]299
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]300<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
301external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]302
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]303</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]304</div>
305
306<!-- _______________________________________________________________________ -->
307<div class="doc_subsubsection">
308 Notes
309</div>
310
311<div class="doc_text">
312
313<ul>
314
315<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]316
317<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]318support for floating point data types of any size other than 32 and 64
319bits.</li>
320
321<li>The following Unix system functionality has not been tested and may not
322work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]323 <ol>
324 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
325 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
326 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
327 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
328 - These functions have not been tested.
329 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]330
331<li>Although many GCC extensions are supported, some are not. In particular,
332 the following extensions are known to <b>not be</b> supported:
333 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]334 <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]335 <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>
336 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
337 <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]338 <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]339 <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>
340 <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]341 <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>
342 <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>
343 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
344 <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]345 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]346
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]347 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]348 attribute means that the LLVM compiler ignores the presence of the attribute,
349 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]350 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]351 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]352
353 <ol>
354 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
355 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]356 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]357
358 <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]359
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]360 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]361 return.<br>
362
363 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
364 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
365 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
366
367 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
368 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
369 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
370
371 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
372 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
373 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]374
375 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
376 Specifying attributes of variables.<br>
377 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
378 <tt>deprecated</tt>, <tt>transparent_union</tt>,
379 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]380
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]381 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
382 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
383 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]384 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]385
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]386 <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]387 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]388 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]389
390 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
391 all target specific attributes.</li>
392
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]393 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
394 Other built-in functions.<br>
395 We support all builtins which have a C language equivalent (e.g.,
396 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
397 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]398 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
399 (currently ignored). We also support builtins for ISO C99 floating
400 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]401 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]402
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]403 <p>The following extensions <b>are</b> known to be supported:</p>
404
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]405 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]406 <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]407 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
408 <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]409 <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]410 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
411 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
412 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
413 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
414 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
415 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
416 <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>
417 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
418 <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]419 <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]420 <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]421 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
422or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]423 <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]424 <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]425 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
426 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
427 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
428 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
429 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
430 <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>
431 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
432 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
433 <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>
434 <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>
435 <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]436 <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]437 <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>
438 <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]439 </ol></li>
440
441</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]442
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]443<p>If you run into GCC extensions which have not been included in any of these
444lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]445
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]446</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]447
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]448<!-- ======================================================================= -->
449<div class="doc_subsection">
450 <a name="c++-fe">Known problems with the C++ front-end</a>
451</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]452
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]453<div class="doc_text">
454
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]455<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]456has not been tested as thoroughly as the C front-end. It has been tested and
457works for a number of non-trivial programs, but there may be lurking bugs.
458Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]459
460</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]461
462<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]463<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]464
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]465<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]466
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]467<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]468<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]469 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]470
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]471<li><b>IA-64 specific</b>: The C++ front-end does not use <a
472href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]473In particular, it just stores function pointers instead of function
474descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]475LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]476
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]477</ul>
478
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]479</div>
480
481<!-- _______________________________________________________________________ -->
482<div class="doc_subsubsection">
483 Notes
484</div>
485
486<div class="doc_text">
487
488<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]489
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]490<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
491parser is significantly more standards compliant (and picky) than prior GCC
492versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]493href="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]494
495<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]496 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]497 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]498 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]499 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]500
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]501<li>The LLVM C++ front-end follows the <a
502 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
503 This document, which is not Itanium specific, specifies a standard for name
504 mangling, class layout, v-table layout, RTTI formats, and other C++
505 representation issues. Because we use this API, code generated by the LLVM
506 compilers should be binary compatible with machine code generated by other
507 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
508 <i>However</i>, the exception handling mechanism used by LLVM is very
509 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]510 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]511
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]512</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]513
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]514</div>
515
516<!-- ======================================================================= -->
517<div class="doc_subsection">
518 <a name="x86-be">Known problems with the X86 back-end</a>
519</div>
520
521<div class="doc_text">
522
523<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]524 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]525</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]526
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]527</div>
528
529<!-- ======================================================================= -->
530<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]531 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]532</div>
533
534<div class="doc_text">
535
536<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]537<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
538several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]539</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]540
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]541</div>
542
543<!-- ======================================================================= -->
544<div class="doc_subsection">
545 <a name="c-be">Known problems with the C back-end</a>
546</div>
547
548<div class="doc_text">
549
550<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]551
552<li>The C back-end produces code that violates the ANSI C Type-Based Alias
553Analysis rules. As such, special options may be necessary to compile the code
554(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]555problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]556
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]557<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]558cannot include special floating point numbers like Not-A-Number or
559Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]560
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]561<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]562supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]563frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]564
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]565</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]566
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]567</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]568
569<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]570<div class="doc_section">
571 <a name="additionalinfo">Additional Information</a>
572</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]573<!-- *********************************************************************** -->
574
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]575<div class="doc_text">
576
577<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]578including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]579implemented in LLVM. The web page also contains versions of the API
580documentation which is up-to-date with the CVS version of the source code. You
581can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]582the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]583
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]584<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]585us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
586lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]587
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]588</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]589
590<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]591
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]592<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]593<address>
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598
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]599 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]600 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]601</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]602
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]603</body>
604</html>