Gitiles
Code Review Sign In
gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 882b8cd493264fd23136e350e4cc2d26abb32249 / . / docs / ReleaseNotes.html
blob: f62783dad83225842a08038d3cd83d3a7793082e [file] [log] [blame]
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2 "http://www.w3.org/TR/html4/strict.dtd">
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 Lattnerf67fb192004-11-18 21:25:11 +0000[diff] [blame]111 <li>llvmgcc and llvmg++ now emit source line number information when '-g' is
112 passed in. This information can be used with llvm-db or other tools and
113 passes.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]114</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]115
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]116</div>
117
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]118
119<!--=========================================================================-->
120<div class="doc_subsubsection">
121In this release, the following missing features were implemented:
122</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]123
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]124<div class="doc_text">
125
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]126<ol>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]127 <li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
Misha Brukmana04d0a12004-10-16 19:13:58 +0000[diff] [blame]128 arbitrary calls</a></li>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]129 <li>The <tt>llvm-ar</tt> tool was previously incomplete and didn't properly
130 support other ar(1) implementations. This has been corrected. <tt>llvm-ar</tt>
131 now fully supports all archive editing functions, table of contents listing,
132 extraction, and printing. It can also read BSD4.4/MacOSX and SVR4 style
133 archives. See <a
134 href="http://llvm.cs.uiuc.edu/docs/CommandGuide/html/llvm-ar.html">llvm-ar</a>
135 for details.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]136</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]137
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]138</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]139
140<!--=========================================================================-->
141<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]142<a name="qualityofimp">In this release, the following Quality of Implementation
143issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]144</div>
145
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]146<div class="doc_text">
147
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]148<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]149<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]150 linking to libstdc++</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]151<li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
Chris Lattner57d43e12004-09-19 19:21:26 +0000[diff] [blame]152 include/llvm/{Support,Config}</a></li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]153</ol>
154
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]155</div>
156
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]157<!--=========================================================================-->
158<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]159In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]160</div>
161
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]162<div class="doc_text">
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]163<ol>
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]164<li></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]165</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]166</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]167
168<!--=========================================================================-->
169<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]170<a name="codequality">This release includes the following Code Quality
171improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]172</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]173
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]174<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]175<ol>
Chris Lattnerffd9cef2004-10-09 19:37:02 +0000[diff] [blame]176<li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
Chris Lattner57d43e12004-09-19 19:21:26 +0000[diff] [blame]177 std::min/std::max</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]178</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]179</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]180
181<!--=========================================================================-->
182<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]183<a name="bugfix">In this release, the following bugs in the previous release
184were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]185</div>
186
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]187<div class="doc_text">
188
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]189<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]190
191<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]192<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]193 and uses broken information</a> (optimizer crash)</li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]194<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]195 functions with lots of values</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]196<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]197 broken in LLVM 1.3</a></li>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]198<li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction tables
Reid Spencerb810d5f2004-08-27 00:48:26 +0000[diff] [blame]199 defined</a></li>
Chris Lattnera2a394f2004-10-25 22:13:02 +0000[diff] [blame]200<li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions w/certain
201 names tickles GNU 'as' bugs</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]202</ol>
203
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]204<p>Bugs in the C/C++ front-end:</p>
205
206<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]207<li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are instantiated</a></li>
208<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]209marked 'constant' if they have nontrivial ctors or dtors</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]210</ol>
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]211
212<p>Bugs fixed in the Sparc V9 back-end:</p>
213
214<ol>
Chris Lattner9cfa0d92004-10-09 19:19:57 +0000[diff] [blame]215<li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]216 failure with certain indirect calls</a></li>
217</ol>
218
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]219</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]220
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]221<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]222<div class="doc_section">
223 <a name="portability">Portability and Supported Platforms</a>
224</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]225<!-- *********************************************************************** -->
226
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]227<div class="doc_text">
228
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]229<p>LLVM is known to work in the following platforms:</p>
230
231<ul>
232<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
233 other unix-like systems).</li>
234<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]235<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnere58d3562004-08-05 21:53:13 +0000[diff] [blame]236<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
237support is available yet, and LLC support is beta. The C backend can be used
238to produce stable code for this platform.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]239</ul>
240
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]241<p>The core LLVM infrastructure uses
242<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
243to the machine and operating system on which it is built. However, minor
244porting may be required to get LLVM to work on new platforms. We welcome your
245portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]246
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]247<p>Note that the LLVM build system does not currently support directories with
248spaces on them when running on Win32/cygwin. We strongly recommend running
249LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]250<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
251cygwin packages. By default, many important tools are not installed that
Chris Lattner5aff3552004-08-16 20:20:46 +0000[diff] [blame]252are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
253please make sure that there are no directories with spaces in them in your
254PATH environment variable.</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]255
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]256</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]257
258<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]259<div class="doc_section">
260 <a name="knownproblems">Known Problems</a>
261</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]262<!-- *********************************************************************** -->
263
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]264<div class="doc_text">
265
266<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]267component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]268sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]269href="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]270there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]271
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]272</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]273
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]274<!-- ======================================================================= -->
275<div class="doc_subsection">
276 <a name="experimental">Experimental features included with this release</a>
277</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]278
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]279<div class="doc_text">
280
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]281<p>The following components of this LLVM release are either untested, known to
282be broken or unreliable, or are in early development. These components should
283not be relied on, and bugs should not be filed against them, but they may be
284useful to some people. In particular, if you would like to work on one of these
285components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]286
287<ul>
Misha Brukman94118752004-08-05 21:04:03 +0000[diff] [blame]288<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
289benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
290details.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]291<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner9934f972004-09-14 16:43:13 +0000[diff] [blame]292 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]293<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
294 it should) and not thoroughly tested.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]295<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
296</ul>
297
298</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]299
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]300<!-- ======================================================================= -->
301<div class="doc_subsection">
302 <a name="core">Known problems with the LLVM Core</a>
303</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]304
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]305<div class="doc_text">
306
307<ul>
308
309<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
310work.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]311
312<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]313such, execution of a threaded program could cause these data structures to be
314corrupted.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]315
Chris Lattnereb673962004-08-08 03:33:07 +0000[diff] [blame]316<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]317table in the archive).</li>
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]318
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]319<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
320objects/archives in the order specified on the command line.</a></li>
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]321
322<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]323values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]324targets whose setjmp/longjmp libraries do not save and restore the entire
325register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]326</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]327</div>
328
329<!-- ======================================================================= -->
330<div class="doc_subsection">
331 <a name="c-fe">Known problems with the C front-end</a>
332</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]333
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]334<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]335<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]336
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]337<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]338<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]339<li>C99 Variable sized arrays do not release stack memory when they go out of
340 scope. Thus, the following program may run out of stack space:
341<pre>
342 for (i = 0; i != 1000000; ++i) {
343 int X[n];
344 foo(X);
345 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]346</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]347
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]348<li>Initialization of global union variables can only be done <a
349href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
350member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]351
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]352<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
353external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]354
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]355</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]356</div>
357
358<!-- _______________________________________________________________________ -->
359<div class="doc_subsubsection">
360 Notes
361</div>
362
363<div class="doc_text">
364
365<ul>
366
367<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]368
369<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]370support for floating point data types of any size other than 32 and 64
371bits.</li>
372
373<li>The following Unix system functionality has not been tested and may not
374work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]375 <ol>
376 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
377 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
378 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
379 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
380 - These functions have not been tested.
381 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]382
383<li>Although many GCC extensions are supported, some are not. In particular,
384 the following extensions are known to <b>not be</b> supported:
385 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]386 <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]387 <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>
388 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
389 <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]390 <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]391 <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>
392 <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]393 <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>
394 <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>
395 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
396 <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]397 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]398
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]399 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]400 attribute means that the LLVM compiler ignores the presence of the attribute,
401 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]402 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]403 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]404
405 <ol>
406 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
407 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]408 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]409
410 <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]411
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]412 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]413 return.<br>
414
415 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
416 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
417 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
418
419 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
420 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
421 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
422
423 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
424 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
425 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]426
427 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
428 Specifying attributes of variables.<br>
429 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
430 <tt>deprecated</tt>, <tt>transparent_union</tt>,
431 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]432
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]433 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
434 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
435 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]436 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]437
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]438 <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]439 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]440 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]441
442 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
443 all target specific attributes.</li>
444
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]445 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
446 Other built-in functions.<br>
447 We support all builtins which have a C language equivalent (e.g.,
448 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
449 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]450 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
451 (currently ignored). We also support builtins for ISO C99 floating
452 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]453 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]454
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]455 <p>The following extensions <b>are</b> known to be supported:</p>
456
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]457 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]458 <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]459 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
460 <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]461 <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]462 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
463 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
464 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
465 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
466 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
467 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
468 <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>
469 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
470 <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]471 <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]472 <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]473 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
474or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]475 <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]476 <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]477 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
478 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
479 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
480 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
481 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
482 <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>
483 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
484 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
485 <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>
486 <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>
487 <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]488 <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]489 <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>
490 <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]491 </ol></li>
492
493</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]494
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]495<p>If you run into GCC extensions which have not been included in any of these
496lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]497
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]498</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]499
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]500<!-- ======================================================================= -->
501<div class="doc_subsection">
502 <a name="c++-fe">Known problems with the C++ front-end</a>
503</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]504
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]505<div class="doc_text">
506
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]507<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]508has not been tested as thoroughly as the C front-end. It has been tested and
509works for a number of non-trivial programs, but there may be lurking bugs.
510Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]511
512</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]513
514<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]515<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]516
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]517<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]518
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]519<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]520<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]521 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]522
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]523<li><b>IA-64 specific</b>: The C++ front-end does not use <a
524href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]525In particular, it just stores function pointers instead of function
526descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]527LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]528
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]529</ul>
530
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]531</div>
532
533<!-- _______________________________________________________________________ -->
534<div class="doc_subsubsection">
535 Notes
536</div>
537
538<div class="doc_text">
539
540<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]541
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]542<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
543parser is significantly more standards compliant (and picky) than prior GCC
544versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]545href="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]546
547<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]548 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]549 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]550 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]551 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]552
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]553<li>The LLVM C++ front-end follows the <a
554 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
555 This document, which is not Itanium specific, specifies a standard for name
556 mangling, class layout, v-table layout, RTTI formats, and other C++
557 representation issues. Because we use this API, code generated by the LLVM
558 compilers should be binary compatible with machine code generated by other
559 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
560 <i>However</i>, the exception handling mechanism used by LLVM is very
561 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]562 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]563
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]564</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]565
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]566</div>
567
568<!-- ======================================================================= -->
569<div class="doc_subsection">
570 <a name="x86-be">Known problems with the X86 back-end</a>
571</div>
572
573<div class="doc_text">
574
575<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]576 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]577</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]578
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]579</div>
580
581<!-- ======================================================================= -->
582<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]583 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]584</div>
585
586<div class="doc_text">
587
588<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]589<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
590several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]591</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]592
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]593</div>
594
595<!-- ======================================================================= -->
596<div class="doc_subsection">
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]597 <a name="ppc-be">Known problems with the PowerPC back-end</a>
598</div>
599
600<div class="doc_text">
601
602<ul>
603<li>none yet</li>
604</ul>
605
606</div>
607
608<!-- ======================================================================= -->
609<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]610 <a name="c-be">Known problems with the C back-end</a>
611</div>
612
613<div class="doc_text">
614
615<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]616
617<li>The C back-end produces code that violates the ANSI C Type-Based Alias
618Analysis rules. As such, special options may be necessary to compile the code
619(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]620problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]621
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]622<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]623cannot include special floating point numbers like Not-A-Number or
624Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]625
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]626<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]627supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]628frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]629
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]630</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]631
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]632</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]633
634<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]635<div class="doc_section">
636 <a name="additionalinfo">Additional Information</a>
637</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]638<!-- *********************************************************************** -->
639
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]640<div class="doc_text">
641
642<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]643including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]644implemented in LLVM. The web page also contains versions of the API
645documentation which is up-to-date with the CVS version of the source code. You
646can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]647the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]648
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]649<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]650us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
651lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]652
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]653</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]654
655<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]656
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]657<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]658<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]659 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]660 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
661 <a href="http://validator.w3.org/check/referer"><img
662 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
663
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]664 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]665 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]666</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]667
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]668</body>
669</html>