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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>
Chris Lattner7c8dd7f2004-11-17 18:19:32 +0000[diff] [blame]100 <li>The LLVM source code is much more compatible with Microsoft Visual C++,
101 including the JIT and runtime-code generation, though the entire system
102 may not work with it.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]103</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]104
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]105</div>
106
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]107
108<!--=========================================================================-->
109<div class="doc_subsubsection">
110In this release, the following missing features were implemented:
111</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]112
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]113<div class="doc_text">
114
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]115<ol>
Misha Brukmana04d0a12004-10-16 19:13:58 +0000[diff] [blame]116<li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
117 arbitrary calls</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]118</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]119
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]120</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]121
122<!--=========================================================================-->
123<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]124<a name="qualityofimp">In this release, the following Quality of Implementation
125issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]126</div>
127
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]128<div class="doc_text">
129
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]130<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]131<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]132 linking to libstdc++</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]133<li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
Chris Lattner57d43e12004-09-19 19:21:26 +0000[diff] [blame]134 include/llvm/{Support,Config}</a></li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]135</ol>
136
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]137</div>
138
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]139<!--=========================================================================-->
140<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]141In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]142</div>
143
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]144<div class="doc_text">
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]145<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]146<li></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]147</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]148</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]149
150<!--=========================================================================-->
151<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]152<a name="codequality">This release includes the following Code Quality
153improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]154</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]155
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]156<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]157<ol>
Chris Lattnerffd9cef2004-10-09 19:37:02 +0000[diff] [blame]158<li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
Chris Lattner57d43e12004-09-19 19:21:26 +0000[diff] [blame]159 std::min/std::max</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]160</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]161</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]162
163<!--=========================================================================-->
164<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]165<a name="bugfix">In this release, the following bugs in the previous release
166were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]167</div>
168
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]169<div class="doc_text">
170
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]171<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]172
173<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]174<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]175 and uses broken information</a> (optimizer crash)</li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]176<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]177 functions with lots of values</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]178<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]179 broken in LLVM 1.3</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]180<li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction tables
Reid Spencerb810d5f2004-08-27 00:48:26 +0000[diff] [blame]181 defined</a></li>
Chris Lattnera2a394f2004-10-25 22:13:02 +0000[diff] [blame]182<li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions w/certain
183 names tickles GNU 'as' bugs</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]184</ol>
185
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]186<p>Bugs in the C/C++ front-end:</p>
187
188<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]189<li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are instantiated</a></li>
190<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]191marked 'constant' if they have nontrivial ctors or dtors</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]192</ol>
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]193
194<p>Bugs fixed in the Sparc V9 back-end:</p>
195
196<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]197<li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]198 failure with certain indirect calls</a></li>
199</ol>
200
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]201</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]202
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]203<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]204<div class="doc_section">
205 <a name="portability">Portability and Supported Platforms</a>
206</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]207<!-- *********************************************************************** -->
208
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]209<div class="doc_text">
210
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]211<p>LLVM is known to work in the following platforms:</p>
212
213<ul>
214<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
215 other unix-like systems).</li>
216<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]217<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnere58d3562004-08-05 21:53:13 +0000[diff] [blame]218<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
219support is available yet, and LLC support is beta. The C backend can be used
220to produce stable code for this platform.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]221</ul>
222
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]223<p>The core LLVM infrastructure uses
224<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
225to the machine and operating system on which it is built. However, minor
226porting may be required to get LLVM to work on new platforms. We welcome your
227portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]228
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]229<p>Note that the LLVM build system does not currently support directories with
230spaces on them when running on Win32/cygwin. We strongly recommend running
231LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]232<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
233cygwin packages. By default, many important tools are not installed that
Chris Lattner5aff3552004-08-16 20:20:46 +0000[diff] [blame]234are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
235please make sure that there are no directories with spaces in them in your
236PATH environment variable.</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]237
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]238</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]239
240<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]241<div class="doc_section">
242 <a name="knownproblems">Known Problems</a>
243</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]244<!-- *********************************************************************** -->
245
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]246<div class="doc_text">
247
248<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]249component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]250sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]251href="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]252there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]253
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]254</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]255
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]256<!-- ======================================================================= -->
257<div class="doc_subsection">
258 <a name="experimental">Experimental features included with this release</a>
259</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]260
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]261<div class="doc_text">
262
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]263<p>The following components of this LLVM release are either untested, known to
264be broken or unreliable, or are in early development. These components should
265not be relied on, and bugs should not be filed against them, but they may be
266useful to some people. In particular, if you would like to work on one of these
267components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]268
269<ul>
Misha Brukman94118752004-08-05 21:04:03 +0000[diff] [blame]270<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
271benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
272details.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]273<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner9934f972004-09-14 16:43:13 +0000[diff] [blame]274 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]275<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
276 it should) and not thoroughly tested.</li>
277<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
278<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
279</ul>
280
281</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]282
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]283<!-- ======================================================================= -->
284<div class="doc_subsection">
285 <a name="core">Known problems with the LLVM Core</a>
286</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]287
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]288<div class="doc_text">
289
290<ul>
291
292<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
293work.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]294
295<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]296such, execution of a threaded program could cause these data structures to be
297corrupted.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]298
Chris Lattnereb673962004-08-08 03:33:07 +0000[diff] [blame]299<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]300table in the archive).</li>
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]301
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]302<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
303objects/archives in the order specified on the command line.</a></li>
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]304
305<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]306values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]307targets whose setjmp/longjmp libraries do not save and restore the entire
308register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]309</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]310</div>
311
312<!-- ======================================================================= -->
313<div class="doc_subsection">
314 <a name="c-fe">Known problems with the C front-end</a>
315</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]316
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]317<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]318<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]319
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]320<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]321<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]322<li>C99 Variable sized arrays do not release stack memory when they go out of
323 scope. Thus, the following program may run out of stack space:
324<pre>
325 for (i = 0; i != 1000000; ++i) {
326 int X[n];
327 foo(X);
328 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]329</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]330
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]331<li>Initialization of global union variables can only be done <a
332href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
333member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]334
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]335<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
336external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]337
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]338</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]339</div>
340
341<!-- _______________________________________________________________________ -->
342<div class="doc_subsubsection">
343 Notes
344</div>
345
346<div class="doc_text">
347
348<ul>
349
350<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]351
352<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]353support for floating point data types of any size other than 32 and 64
354bits.</li>
355
356<li>The following Unix system functionality has not been tested and may not
357work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]358 <ol>
359 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
360 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
361 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
362 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
363 - These functions have not been tested.
364 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]365
366<li>Although many GCC extensions are supported, some are not. In particular,
367 the following extensions are known to <b>not be</b> supported:
368 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]369 <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]370 <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>
371 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
372 <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]373 <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]374 <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>
375 <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]376 <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>
377 <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>
378 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
379 <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]380 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]381
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]382 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]383 attribute means that the LLVM compiler ignores the presence of the attribute,
384 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]385 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]386 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]387
388 <ol>
389 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
390 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]391 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]392
393 <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]394
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]395 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]396 return.<br>
397
398 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
399 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
400 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
401
402 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
403 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
404 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
405
406 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
407 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
408 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]409
410 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
411 Specifying attributes of variables.<br>
412 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
413 <tt>deprecated</tt>, <tt>transparent_union</tt>,
414 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]415
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]416 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
417 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
418 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]419 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]420
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]421 <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]422 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]423 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]424
425 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
426 all target specific attributes.</li>
427
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]428 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
429 Other built-in functions.<br>
430 We support all builtins which have a C language equivalent (e.g.,
431 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
432 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]433 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
434 (currently ignored). We also support builtins for ISO C99 floating
435 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]436 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]437
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]438 <p>The following extensions <b>are</b> known to be supported:</p>
439
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]440 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]441 <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]442 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
443 <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]444 <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]445 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
446 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
447 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
448 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
449 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
450 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
451 <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>
452 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
453 <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]454 <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]455 <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]456 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
457or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]458 <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]459 <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]460 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
461 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
462 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
463 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
464 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
465 <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>
466 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
467 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
468 <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>
469 <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>
470 <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]471 <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]472 <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>
473 <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]474 </ol></li>
475
476</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]477
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]478<p>If you run into GCC extensions which have not been included in any of these
479lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]480
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]481</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]482
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]483<!-- ======================================================================= -->
484<div class="doc_subsection">
485 <a name="c++-fe">Known problems with the C++ front-end</a>
486</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]487
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]488<div class="doc_text">
489
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]490<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]491has not been tested as thoroughly as the C front-end. It has been tested and
492works for a number of non-trivial programs, but there may be lurking bugs.
493Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]494
495</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]496
497<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]498<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]499
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]500<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]501
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]502<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]503<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]504 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]505
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]506<li><b>IA-64 specific</b>: The C++ front-end does not use <a
507href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]508In particular, it just stores function pointers instead of function
509descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]510LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]511
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]512</ul>
513
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]514</div>
515
516<!-- _______________________________________________________________________ -->
517<div class="doc_subsubsection">
518 Notes
519</div>
520
521<div class="doc_text">
522
523<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]524
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]525<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
526parser is significantly more standards compliant (and picky) than prior GCC
527versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]528href="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]529
530<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]531 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]532 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]533 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]534 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]535
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]536<li>The LLVM C++ front-end follows the <a
537 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
538 This document, which is not Itanium specific, specifies a standard for name
539 mangling, class layout, v-table layout, RTTI formats, and other C++
540 representation issues. Because we use this API, code generated by the LLVM
541 compilers should be binary compatible with machine code generated by other
542 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
543 <i>However</i>, the exception handling mechanism used by LLVM is very
544 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]545 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]546
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]547</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]548
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]549</div>
550
551<!-- ======================================================================= -->
552<div class="doc_subsection">
553 <a name="x86-be">Known problems with the X86 back-end</a>
554</div>
555
556<div class="doc_text">
557
558<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]559 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]560</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]561
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]562</div>
563
564<!-- ======================================================================= -->
565<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]566 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]567</div>
568
569<div class="doc_text">
570
571<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]572<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
573several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]574</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]575
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]576</div>
577
578<!-- ======================================================================= -->
579<div class="doc_subsection">
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]580 <a name="ppc-be">Known problems with the PowerPC back-end</a>
581</div>
582
583<div class="doc_text">
584
585<ul>
586<li>none yet</li>
587</ul>
588
589</div>
590
591<!-- ======================================================================= -->
592<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]593 <a name="c-be">Known problems with the C back-end</a>
594</div>
595
596<div class="doc_text">
597
598<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]599
600<li>The C back-end produces code that violates the ANSI C Type-Based Alias
601Analysis rules. As such, special options may be necessary to compile the code
602(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]603problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]604
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]605<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]606cannot include special floating point numbers like Not-A-Number or
607Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]608
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]609<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]610supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]611frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]612
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]613</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]614
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]615</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]616
617<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]618<div class="doc_section">
619 <a name="additionalinfo">Additional Information</a>
620</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]621<!-- *********************************************************************** -->
622
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]623<div class="doc_text">
624
625<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]626including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]627implemented in LLVM. The web page also contains versions of the API
628documentation which is up-to-date with the CVS version of the source code. You
629can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]630the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]631
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]632<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]633us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
634lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]635
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]636</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]637
638<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]639
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]640<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]641<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]642 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]643 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
644 <a href="http://validator.w3.org/check/referer"><img
645 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
646
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]647 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]648 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]649</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]650
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]651</body>
652</html>