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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 6454ed3c1e3b737a1137286223e3737d65251e66 / . / docs / ReleaseNotes.html
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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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3<html>
4<head>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame^]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]6 <link rel="stylesheet" href="llvm.css" type="text/css">
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]7 <title>LLVM 1.4 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]10
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]11<div class="doc_title">LLVM 1.4 Release Notes</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]12
13<ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]14 <li><a href="#intro">Introduction</a></li>
15 <li><a href="#whatsnew">What's New?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]16 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]18 <li><a href="#knownproblems">Known Problems</a>
19 <ul>
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]20 <li><a href="#experimental">Experimental features included in this
21 release</a>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]22 <li><a href="#core">Known problems with the LLVM Core</a>
23 <li><a href="#c-fe">Known problems with the C Front-end</a>
24 <li><a href="#c++-fe">Known problems with the C++ Front-end</a>
25 <li><a href="#x86-be">Known problems with the X86 Back-end</a>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]26 <li><a href="#sparcv9-be">Known problems with the SparcV9 Back-end</a>
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]27 <li><a href="#ppc-be">Known problems with the PowerPC Back-end</a>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]28 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]29 </ul></li>
30 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]31</ol>
32
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]33<div class="doc_author">
34 <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]35</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]36
37<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]38<div class="doc_section">
39 <a name="intro">Introduction</a>
40</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]41<!-- *********************************************************************** -->
42
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]43<div class="doc_text">
44
45<p>This document contains the release notes for the LLVM compiler
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]46infrastructure, release 1.4. Here we describe the status of LLVM, including any
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]47known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]48version of this document can be found on the <a
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]49href="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]50not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]51this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]52
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]53<p>For more information about LLVM, including information about potentially more
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]54current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main
55web site</a>. If you have questions or comments, the <a
56href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]57list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]58
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]59<p>Note that if you are reading this file from CVS, this document applies
60to the <i>next</i> release, not the current one. To see the release notes for
61the current or previous releases, see the <a
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]62href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
63
64</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]65
66<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]67<div class="doc_section">
68 <a name="whatsnew">What's New?</a>
69</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]70<!-- *********************************************************************** -->
71
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]72<div class="doc_text">
73
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]74<p>This is the fifth public release of the LLVM compiler infrastructure.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]75
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]76<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]77SPEC CPU95 &amp; 2000 benchmarks, the Olden benchmarks, and the Ptrdist
Chris Lattner9b3b04f2004-10-16 18:35:57 +0000[diff] [blame]78benchmarks, and <b>many</b> other C and C++ programs.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]79
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]80</div>
81
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]82<!--=========================================================================-->
83<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]84<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]85</div>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]86
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]87<div class="doc_text">
88
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]89<ol>
Misha Brukmana04d0a12004-10-16 19:13:58 +0000[diff] [blame]90 <li>The test/Programs hierarchy <a href="http://llvm.cs.uiuc.edu/PR257">has
Chris Lattner9b3b04f2004-10-16 18:35:57 +0000[diff] [blame]91 been moved out of the main LLVM tree</a> into a separate CVS repo and
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame^]92 tarball. This shrinks the distribution size of LLVM itself dramatically.
93 </li>
Chris Lattner9b3b04f2004-10-16 18:35:57 +0000[diff] [blame]94 <li>LLVM now optimizes global variables significantly more than it did
95 before.</li>
96 <li>LLVM now includes the new '<tt>undef</tt>' value and <a
97 href="LangRef.html#i_unreachable"><tt>unreachable</tt></a> instruction,
98 which give the optimizer more information about the behavior of the
99 program.</li>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame^]100 <li>The LLVM makefiles have been improved to build LLVM much faster (2x) and
101 includes new targets (like dist-check, uninstall). One important change is
102 associated with <a href="http://llvm.cs.uiuc.edu/PR456>PR456">PR456</a>.
103 The libraries and tools will now be built into
104 <tt>$builddir/Debug/{bin,lib}</tt> instead of
105 <tt>$builddir/tools/Debug</tt> and <tt>$builddir/lib/Debug</tt>. Similarly
106 for <tt>Release</tt> and <tt>Profile</tt> builds.
107 </li>
Chris Lattner7c8dd7f2004-11-17 18:19:32 +0000[diff] [blame]108 <li>The LLVM source code is much more compatible with Microsoft Visual C++,
109 including the JIT and runtime-code generation, though the entire system
110 may not work with it.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]111</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]112
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]113</div>
114
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]115
116<!--=========================================================================-->
117<div class="doc_subsubsection">
118In this release, the following missing features were implemented:
119</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]120
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]121<div class="doc_text">
122
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]123<ol>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame^]124 <li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
Misha Brukmana04d0a12004-10-16 19:13:58 +0000[diff] [blame]125 arbitrary calls</a></li>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame^]126 <li>The <tt>llvm-ar</tt> tool was previously incomplete and didn't properly
127 support other ar(1) implementations. This has been corrected. <tt>llvm-ar</tt>
128 now fully supports all archive editing functions, table of contents listing,
129 extraction, and printing. It can also read BSD4.4/MacOSX and SVR4 style
130 archives. See <a
131 href="http://llvm.cs.uiuc.edu/docs/CommandGuide/html/llvm-ar.html">llvm-ar</a>
132 for details.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]133</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]134
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]135</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]136
137<!--=========================================================================-->
138<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]139<a name="qualityofimp">In this release, the following Quality of Implementation
140issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]141</div>
142
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]143<div class="doc_text">
144
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]145<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]146<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]147 linking to libstdc++</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]148<li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
Chris Lattner57d43e12004-09-19 19:21:26 +0000[diff] [blame]149 include/llvm/{Support,Config}</a></li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]150</ol>
151
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]152</div>
153
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]154<!--=========================================================================-->
155<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]156In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]157</div>
158
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]159<div class="doc_text">
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]160<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]161<li></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]162</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]163</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]164
165<!--=========================================================================-->
166<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]167<a name="codequality">This release includes the following Code Quality
168improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]169</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]170
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]171<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]172<ol>
Chris Lattnerffd9cef2004-10-09 19:37:02 +0000[diff] [blame]173<li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
Chris Lattner57d43e12004-09-19 19:21:26 +0000[diff] [blame]174 std::min/std::max</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]175</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]176</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]177
178<!--=========================================================================-->
179<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]180<a name="bugfix">In this release, the following bugs in the previous release
181were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]182</div>
183
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]184<div class="doc_text">
185
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]186<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]187
188<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]189<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]190 and uses broken information</a> (optimizer crash)</li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]191<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]192 functions with lots of values</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]193<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]194 broken in LLVM 1.3</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]195<li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction tables
Reid Spencerb810d5f2004-08-27 00:48:26 +0000[diff] [blame]196 defined</a></li>
Chris Lattnera2a394f2004-10-25 22:13:02 +0000[diff] [blame]197<li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions w/certain
198 names tickles GNU 'as' bugs</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]199</ol>
200
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]201<p>Bugs in the C/C++ front-end:</p>
202
203<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]204<li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are instantiated</a></li>
205<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]206marked 'constant' if they have nontrivial ctors or dtors</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]207</ol>
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]208
209<p>Bugs fixed in the Sparc V9 back-end:</p>
210
211<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]212<li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]213 failure with certain indirect calls</a></li>
214</ol>
215
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]216</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]217
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]218<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]219<div class="doc_section">
220 <a name="portability">Portability and Supported Platforms</a>
221</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]222<!-- *********************************************************************** -->
223
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]224<div class="doc_text">
225
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]226<p>LLVM is known to work in the following platforms:</p>
227
228<ul>
229<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
230 other unix-like systems).</li>
231<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]232<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnere58d3562004-08-05 21:53:13 +0000[diff] [blame]233<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
234support is available yet, and LLC support is beta. The C backend can be used
235to produce stable code for this platform.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]236</ul>
237
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]238<p>The core LLVM infrastructure uses
239<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
240to the machine and operating system on which it is built. However, minor
241porting may be required to get LLVM to work on new platforms. We welcome your
242portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]243
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]244<p>Note that the LLVM build system does not currently support directories with
245spaces on them when running on Win32/cygwin. We strongly recommend running
246LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]247<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
248cygwin packages. By default, many important tools are not installed that
Chris Lattner5aff3552004-08-16 20:20:46 +0000[diff] [blame]249are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
250please make sure that there are no directories with spaces in them in your
251PATH environment variable.</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]252
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]253</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]254
255<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]256<div class="doc_section">
257 <a name="knownproblems">Known Problems</a>
258</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]259<!-- *********************************************************************** -->
260
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]261<div class="doc_text">
262
263<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]264component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]265sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]266href="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]267there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]268
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]269</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]270
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]271<!-- ======================================================================= -->
272<div class="doc_subsection">
273 <a name="experimental">Experimental features included with this release</a>
274</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]275
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]276<div class="doc_text">
277
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]278<p>The following components of this LLVM release are either untested, known to
279be broken or unreliable, or are in early development. These components should
280not be relied on, and bugs should not be filed against them, but they may be
281useful to some people. In particular, if you would like to work on one of these
282components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]283
284<ul>
Misha Brukman94118752004-08-05 21:04:03 +0000[diff] [blame]285<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
286benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
287details.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]288<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner9934f972004-09-14 16:43:13 +0000[diff] [blame]289 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]290<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
291 it should) and not thoroughly tested.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]292<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
293</ul>
294
295</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]296
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]297<!-- ======================================================================= -->
298<div class="doc_subsection">
299 <a name="core">Known problems with the LLVM Core</a>
300</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]301
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]302<div class="doc_text">
303
304<ul>
305
306<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
307work.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]308
309<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]310such, execution of a threaded program could cause these data structures to be
311corrupted.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]312
Chris Lattnereb673962004-08-08 03:33:07 +0000[diff] [blame]313<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]314table in the archive).</li>
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]315
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]316<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
317objects/archives in the order specified on the command line.</a></li>
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]318
319<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]320values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]321targets whose setjmp/longjmp libraries do not save and restore the entire
322register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]323</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]324</div>
325
326<!-- ======================================================================= -->
327<div class="doc_subsection">
328 <a name="c-fe">Known problems with the C front-end</a>
329</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]330
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]331<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]332<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]333
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]334<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]335<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]336<li>C99 Variable sized arrays do not release stack memory when they go out of
337 scope. Thus, the following program may run out of stack space:
338<pre>
339 for (i = 0; i != 1000000; ++i) {
340 int X[n];
341 foo(X);
342 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]343</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]344
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]345<li>Initialization of global union variables can only be done <a
346href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
347member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]348
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]349<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
350external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]351
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]352</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]353</div>
354
355<!-- _______________________________________________________________________ -->
356<div class="doc_subsubsection">
357 Notes
358</div>
359
360<div class="doc_text">
361
362<ul>
363
364<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]365
366<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]367support for floating point data types of any size other than 32 and 64
368bits.</li>
369
370<li>The following Unix system functionality has not been tested and may not
371work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]372 <ol>
373 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
374 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
375 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
376 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
377 - These functions have not been tested.
378 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]379
380<li>Although many GCC extensions are supported, some are not. In particular,
381 the following extensions are known to <b>not be</b> supported:
382 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]383 <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]384 <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>
385 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
386 <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]387 <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]388 <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>
389 <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]390 <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>
391 <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>
392 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
393 <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]394 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]395
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]396 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]397 attribute means that the LLVM compiler ignores the presence of the attribute,
398 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]399 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]400 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]401
402 <ol>
403 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
404 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]405 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]406
407 <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]408
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]409 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]410 return.<br>
411
412 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
413 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
414 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
415
416 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
417 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
418 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
419
420 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
421 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
422 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]423
424 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
425 Specifying attributes of variables.<br>
426 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
427 <tt>deprecated</tt>, <tt>transparent_union</tt>,
428 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]429
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]430 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
431 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
432 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]433 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]434
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]435 <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]436 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]437 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]438
439 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
440 all target specific attributes.</li>
441
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]442 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
443 Other built-in functions.<br>
444 We support all builtins which have a C language equivalent (e.g.,
445 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
446 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]447 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
448 (currently ignored). We also support builtins for ISO C99 floating
449 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]450 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]451
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]452 <p>The following extensions <b>are</b> known to be supported:</p>
453
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]454 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]455 <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]456 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
457 <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]458 <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]459 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
460 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
461 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
462 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
463 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
464 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
465 <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>
466 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
467 <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]468 <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]469 <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]470 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
471or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]472 <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]473 <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]474 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
475 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
476 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
477 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
478 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
479 <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>
480 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
481 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
482 <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>
483 <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>
484 <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]485 <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]486 <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>
487 <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]488 </ol></li>
489
490</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]491
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]492<p>If you run into GCC extensions which have not been included in any of these
493lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]494
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]495</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]496
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]497<!-- ======================================================================= -->
498<div class="doc_subsection">
499 <a name="c++-fe">Known problems with the C++ front-end</a>
500</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]501
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]502<div class="doc_text">
503
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]504<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]505has not been tested as thoroughly as the C front-end. It has been tested and
506works for a number of non-trivial programs, but there may be lurking bugs.
507Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]508
509</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]510
511<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]512<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]513
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]514<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]515
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]516<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]517<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]518 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]519
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]520<li><b>IA-64 specific</b>: The C++ front-end does not use <a
521href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]522In particular, it just stores function pointers instead of function
523descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]524LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]525
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]526</ul>
527
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]528</div>
529
530<!-- _______________________________________________________________________ -->
531<div class="doc_subsubsection">
532 Notes
533</div>
534
535<div class="doc_text">
536
537<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]538
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]539<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
540parser is significantly more standards compliant (and picky) than prior GCC
541versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]542href="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]543
544<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]545 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]546 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]547 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]548 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]549
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]550<li>The LLVM C++ front-end follows the <a
551 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
552 This document, which is not Itanium specific, specifies a standard for name
553 mangling, class layout, v-table layout, RTTI formats, and other C++
554 representation issues. Because we use this API, code generated by the LLVM
555 compilers should be binary compatible with machine code generated by other
556 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
557 <i>However</i>, the exception handling mechanism used by LLVM is very
558 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]559 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]560
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]561</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]562
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]563</div>
564
565<!-- ======================================================================= -->
566<div class="doc_subsection">
567 <a name="x86-be">Known problems with the X86 back-end</a>
568</div>
569
570<div class="doc_text">
571
572<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]573 <li>none yet</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">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]580 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]581</div>
582
583<div class="doc_text">
584
585<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]586<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
587several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]588</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]589
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]590</div>
591
592<!-- ======================================================================= -->
593<div class="doc_subsection">
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]594 <a name="ppc-be">Known problems with the PowerPC back-end</a>
595</div>
596
597<div class="doc_text">
598
599<ul>
600<li>none yet</li>
601</ul>
602
603</div>
604
605<!-- ======================================================================= -->
606<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]607 <a name="c-be">Known problems with the C back-end</a>
608</div>
609
610<div class="doc_text">
611
612<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]613
614<li>The C back-end produces code that violates the ANSI C Type-Based Alias
615Analysis rules. As such, special options may be necessary to compile the code
616(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]617problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]618
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]619<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]620cannot include special floating point numbers like Not-A-Number or
621Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]622
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]623<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]624supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]625frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]626
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]627</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]628
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]629</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]630
631<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]632<div class="doc_section">
633 <a name="additionalinfo">Additional Information</a>
634</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]635<!-- *********************************************************************** -->
636
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]637<div class="doc_text">
638
639<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]640including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]641implemented in LLVM. The web page also contains versions of the API
642documentation which is up-to-date with the CVS version of the source code. You
643can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]644the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]645
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]646<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]647us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
648lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]649
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]650</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]651
652<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]653
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]654<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]655<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]656 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]657 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
658 <a href="http://validator.w3.org/check/referer"><img
659 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
660
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]661 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]662 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]663</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]664
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]665</body>
666</html>