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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 Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]26 <li><a href="#ppc-be">Known problems with the PowerPC Back-end</a>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]27 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]28 </ul></li>
29 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]30</ol>
31
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]32<div class="doc_author">
33 <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]34</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]35
36<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]37<div class="doc_section">
38 <a name="intro">Introduction</a>
39</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]40<!-- *********************************************************************** -->
41
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]42<div class="doc_text">
43
44<p>This document contains the release notes for the LLVM compiler
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]45infrastructure, release 1.4. Here we describe the status of LLVM, including any
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]46known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]47version of this document can be found on the <a
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]48href="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]49not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]50this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]51
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]52<p>For more information about LLVM, including information about potentially more
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]53current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main
54web site</a>. If you have questions or comments, the <a
55href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]56list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]57
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]58<p>Note that if you are reading this file from CVS, this document applies
59to the <i>next</i> release, not the current one. To see the release notes for
60the current or previous releases, see the <a
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]61href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
62
63</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]64
65<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]66<div class="doc_section">
67 <a name="whatsnew">What's New?</a>
68</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]69<!-- *********************************************************************** -->
70
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]71<div class="doc_text">
72
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]73<p>This is the fifth public release of the LLVM compiler infrastructure.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]74
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]75<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]76SPEC CPU95 &amp; 2000 benchmarks, the Olden benchmarks, and the Ptrdist
Chris Lattner9b3b04f2004-10-16 18:35:57 +0000[diff] [blame]77benchmarks, and <b>many</b> other C and 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>
Misha Brukmana04d0a12004-10-16 19:13:58 +0000[diff] [blame]89 <li>The test/Programs hierarchy <a href="http://llvm.cs.uiuc.edu/PR257">has
Chris Lattner9b3b04f2004-10-16 18:35:57 +0000[diff] [blame]90 been moved out of the main LLVM tree</a> into a separate CVS repo and
91 tarball.</li>
92 <li>LLVM now optimizes global variables significantly more than it did
93 before.</li>
94 <li>LLVM now includes the new '<tt>undef</tt>' value and <a
95 href="LangRef.html#i_unreachable"><tt>unreachable</tt></a> instruction,
96 which give the optimizer more information about the behavior of the
97 program.</li>
Chris Lattnerf1ccf1a2004-10-27 16:28:17 +0000[diff] [blame]98 <li>The LLVM makefiles have been improved to build LLVM much faster and
99 includes new targets (like make dist-check).</li>
100 <li>The LLVM source code is now compatible with Microsoft Visual C++.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]101</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]102
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]103</div>
104
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]105
106<!--=========================================================================-->
107<div class="doc_subsubsection">
108In this release, the following missing features were implemented:
109</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]110
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]111<div class="doc_text">
112
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]113<ol>
Misha Brukmana04d0a12004-10-16 19:13:58 +0000[diff] [blame]114<li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
115 arbitrary calls</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]116</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]117
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]118</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]119
120<!--=========================================================================-->
121<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]122<a name="qualityofimp">In this release, the following Quality of Implementation
123issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]124</div>
125
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]126<div class="doc_text">
127
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]128<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]129<li><a href="http://llvm.cs.uiuc.edu/PR426">[llvmg++] Tons of warnings are spewed when
Chris Lattner980c50f2004-08-20 00:36:23 +0000[diff] [blame]130 linking to libstdc++</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]131<li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
Chris Lattner57d43e12004-09-19 19:21:26 +0000[diff] [blame]132 include/llvm/{Support,Config}</a></li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]133</ol>
134
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]135</div>
136
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]137<!--=========================================================================-->
138<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]139In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]140</div>
141
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]142<div class="doc_text">
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]143<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]144<li></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]145</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]146</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]147
148<!--=========================================================================-->
149<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]150<a name="codequality">This release includes the following Code Quality
151improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]152</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]153
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]154<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]155<ol>
Chris Lattnerffd9cef2004-10-09 19:37:02 +0000[diff] [blame]156<li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
Chris Lattner57d43e12004-09-19 19:21:26 +0000[diff] [blame]157 std::min/std::max</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]158</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]159</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]160
161<!--=========================================================================-->
162<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]163<a name="bugfix">In this release, the following bugs in the previous release
164were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]165</div>
166
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]167<div class="doc_text">
168
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]169<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]170
171<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]172<li><a href="http://llvm.cs.uiuc.edu/PR420">[licm] LICM invalidates alias analysis info
Chris Lattner372dc8d2004-09-15 01:09:25 +0000[diff] [blame]173 and uses broken information</a> (optimizer crash)</li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]174<li><a href="http://llvm.cs.uiuc.edu/PR422">[asmwriter] Asmwriter is really slow for
Chris Lattner372dc8d2004-09-15 01:09:25 +0000[diff] [blame]175 functions with lots of values</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]176<li><a href="http://llvm.cs.uiuc.edu/PR423">[anders-aa] Andersen's AA is completely
Chris Lattner446562f2004-08-16 05:46:57 +0000[diff] [blame]177 broken in LLVM 1.3</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]178<li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction tables
Reid Spencerb810d5f2004-08-27 00:48:26 +0000[diff] [blame]179 defined</a></li>
Chris Lattnera2a394f2004-10-25 22:13:02 +0000[diff] [blame]180<li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions w/certain
181 names tickles GNU 'as' bugs</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]182</ol>
183
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]184<p>Bugs in the C/C++ front-end:</p>
185
186<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]187<li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are instantiated</a></li>
188<li><a href="http://llvm.cs.uiuc.edu/PR450">[llvmg++] Extern const globals cannot be
Chris Lattnere4421b42004-10-05 00:23:02 +0000[diff] [blame]189marked 'constant' if they have nontrivial ctors or dtors</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]190</ol>
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]191
192<p>Bugs fixed in the Sparc V9 back-end:</p>
193
194<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]195<li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]196 failure with certain indirect calls</a></li>
197</ol>
198
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]199</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]200
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]201<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]202<div class="doc_section">
203 <a name="portability">Portability and Supported Platforms</a>
204</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]205<!-- *********************************************************************** -->
206
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]207<div class="doc_text">
208
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]209<p>LLVM is known to work in the following platforms:</p>
210
211<ul>
212<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
213 other unix-like systems).</li>
214<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]215<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnere58d3562004-08-05 21:53:13 +0000[diff] [blame]216<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
217support is available yet, and LLC support is beta. The C backend can be used
218to produce stable code for this platform.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]219</ul>
220
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]221<p>The core LLVM infrastructure uses
222<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
223to the machine and operating system on which it is built. However, minor
224porting may be required to get LLVM to work on new platforms. We welcome your
225portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]226
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]227<p>Note that the LLVM build system does not currently support directories with
228spaces on them when running on Win32/cygwin. We strongly recommend running
229LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]230<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
231cygwin packages. By default, many important tools are not installed that
Chris Lattner5aff3552004-08-16 20:20:46 +0000[diff] [blame]232are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
233please make sure that there are no directories with spaces in them in your
234PATH environment variable.</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]235
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]236</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]237
238<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]239<div class="doc_section">
240 <a name="knownproblems">Known Problems</a>
241</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]242<!-- *********************************************************************** -->
243
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]244<div class="doc_text">
245
246<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]247component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]248sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]249href="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]250there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]251
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]252</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]253
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]254<!-- ======================================================================= -->
255<div class="doc_subsection">
256 <a name="experimental">Experimental features included with this release</a>
257</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]258
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]259<div class="doc_text">
260
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]261<p>The following components of this LLVM release are either untested, known to
262be broken or unreliable, or are in early development. These components should
263not be relied on, and bugs should not be filed against them, but they may be
264useful to some people. In particular, if you would like to work on one of these
265components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]266
267<ul>
Misha Brukman94118752004-08-05 21:04:03 +0000[diff] [blame]268<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
269benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
270details.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]271<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner9934f972004-09-14 16:43:13 +0000[diff] [blame]272 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]273<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
274 it should) and not thoroughly tested.</li>
275<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
276<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
277</ul>
278
279</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]280
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]281<!-- ======================================================================= -->
282<div class="doc_subsection">
283 <a name="core">Known problems with the LLVM Core</a>
284</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]285
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]286<div class="doc_text">
287
288<ul>
289
290<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
291work.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]292
293<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]294such, execution of a threaded program could cause these data structures to be
295corrupted.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]296
Chris Lattnereb673962004-08-08 03:33:07 +0000[diff] [blame]297<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]298table in the archive).</li>
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]299
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]300<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
301objects/archives in the order specified on the command line.</a></li>
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]302
303<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]304values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]305targets whose setjmp/longjmp libraries do not save and restore the entire
306register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]307</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]308</div>
309
310<!-- ======================================================================= -->
311<div class="doc_subsection">
312 <a name="c-fe">Known problems with the C front-end</a>
313</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]314
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]315<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]316<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]317
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]318<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]319<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]320<li>C99 Variable sized arrays do not release stack memory when they go out of
321 scope. Thus, the following program may run out of stack space:
322<pre>
323 for (i = 0; i != 1000000; ++i) {
324 int X[n];
325 foo(X);
326 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]327</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]328
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]329<li>Initialization of global union variables can only be done <a
330href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
331member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]332
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]333<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
334external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]335
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]336</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]337</div>
338
339<!-- _______________________________________________________________________ -->
340<div class="doc_subsubsection">
341 Notes
342</div>
343
344<div class="doc_text">
345
346<ul>
347
348<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]349
350<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]351support for floating point data types of any size other than 32 and 64
352bits.</li>
353
354<li>The following Unix system functionality has not been tested and may not
355work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]356 <ol>
357 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
358 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
359 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
360 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
361 - These functions have not been tested.
362 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]363
364<li>Although many GCC extensions are supported, some are not. In particular,
365 the following extensions are known to <b>not be</b> supported:
366 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]367 <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]368 <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>
369 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
370 <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]371 <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]372 <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>
373 <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]374 <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>
375 <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>
376 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
377 <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]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 GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]381 attribute means that the LLVM compiler ignores the presence of the attribute,
382 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]383 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]384 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]385
386 <ol>
387 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
388 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]389 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]390
391 <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]392
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]393 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]394 return.<br>
395
396 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
397 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
398 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
399
400 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
401 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
402 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
403
404 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
405 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
406 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]407
408 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
409 Specifying attributes of variables.<br>
410 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
411 <tt>deprecated</tt>, <tt>transparent_union</tt>,
412 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]413
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]414 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
415 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
416 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]417 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]418
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]419 <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]420 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]421 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]422
423 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
424 all target specific attributes.</li>
425
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]426 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
427 Other built-in functions.<br>
428 We support all builtins which have a C language equivalent (e.g.,
429 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
430 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]431 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
432 (currently ignored). We also support builtins for ISO C99 floating
433 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]434 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]435
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]436 <p>The following extensions <b>are</b> known to be supported:</p>
437
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]438 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]439 <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]440 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
441 <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]442 <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]443 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
444 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
445 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
446 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
447 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
448 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
449 <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>
450 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
451 <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]452 <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]453 <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]454 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
455or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]456 <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]457 <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]458 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
459 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
460 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
461 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
462 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
463 <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>
464 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
465 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
466 <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>
467 <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>
468 <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]469 <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]470 <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>
471 <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]472 </ol></li>
473
474</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]475
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]476<p>If you run into GCC extensions which have not been included in any of these
477lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]478
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]479</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]480
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]481<!-- ======================================================================= -->
482<div class="doc_subsection">
483 <a name="c++-fe">Known problems with the C++ front-end</a>
484</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]485
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]486<div class="doc_text">
487
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]488<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]489has not been tested as thoroughly as the C front-end. It has been tested and
490works for a number of non-trivial programs, but there may be lurking bugs.
491Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]492
493</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]494
495<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]496<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]497
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]498<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]499
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]500<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]501<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]502 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]503
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]504<li><b>IA-64 specific</b>: The C++ front-end does not use <a
505href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]506In particular, it just stores function pointers instead of function
507descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]508LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]509
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]510</ul>
511
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]512</div>
513
514<!-- _______________________________________________________________________ -->
515<div class="doc_subsubsection">
516 Notes
517</div>
518
519<div class="doc_text">
520
521<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]522
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]523<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
524parser is significantly more standards compliant (and picky) than prior GCC
525versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]526href="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]527
528<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]529 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]530 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]531 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]532 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]533
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]534<li>The LLVM C++ front-end follows the <a
535 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
536 This document, which is not Itanium specific, specifies a standard for name
537 mangling, class layout, v-table layout, RTTI formats, and other C++
538 representation issues. Because we use this API, code generated by the LLVM
539 compilers should be binary compatible with machine code generated by other
540 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
541 <i>However</i>, the exception handling mechanism used by LLVM is very
542 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]543 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]544
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]545</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]546
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]547</div>
548
549<!-- ======================================================================= -->
550<div class="doc_subsection">
551 <a name="x86-be">Known problems with the X86 back-end</a>
552</div>
553
554<div class="doc_text">
555
556<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]557 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]558</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]559
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]560</div>
561
562<!-- ======================================================================= -->
563<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]564 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]565</div>
566
567<div class="doc_text">
568
569<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]570<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
571several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]572</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]573
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]574</div>
575
576<!-- ======================================================================= -->
577<div class="doc_subsection">
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]578 <a name="ppc-be">Known problems with the PowerPC back-end</a>
579</div>
580
581<div class="doc_text">
582
583<ul>
584<li>none yet</li>
585</ul>
586
587</div>
588
589<!-- ======================================================================= -->
590<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]591 <a name="c-be">Known problems with the C back-end</a>
592</div>
593
594<div class="doc_text">
595
596<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]597
598<li>The C back-end produces code that violates the ANSI C Type-Based Alias
599Analysis rules. As such, special options may be necessary to compile the code
600(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]601problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]602
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]603<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]604cannot include special floating point numbers like Not-A-Number or
605Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]606
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]607<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]608supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]609frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]610
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]611</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]612
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]613</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]614
615<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]616<div class="doc_section">
617 <a name="additionalinfo">Additional Information</a>
618</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]619<!-- *********************************************************************** -->
620
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]621<div class="doc_text">
622
623<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]624including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]625implemented in LLVM. The web page also contains versions of the API
626documentation which is up-to-date with the CVS version of the source code. You
627can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]628the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]629
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]630<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]631us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
632lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]633
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]634</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]635
636<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]637
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]638<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]639<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]640 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]641 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
642 <a href="http://validator.w3.org/check/referer"><img
643 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
644
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]645 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]646 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]647</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]648
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]649</body>
650</html>