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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">
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]88<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]89 <li>LLVM now optimizes global variables significantly more than it did
90 before.
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]91 </li>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]92 <li>LLVM now includes the new '<tt>undef</tt>' value and
93 <a href="LangRef.html#i_unreachable"><tt>unreachable</tt></a> instruction,
94 which give the optimizer more information about the behavior of the
95 program.
96 </li>
97 <li>llvmgcc and llvmg++ now emit source line number information when '-g' is
98 passed in. This information can be used with llvm-db or other tools and
99 passes.
100 </li>
101 <li>The test/Programs hierarchy <a href="http://llvm.cs.uiuc.edu/PR257">has
102 been moved out of the main LLVM tree</a> into a separate CVS repository and
103 tarball. This shrinks the distribution size of LLVM itself significantly.
104 </li>
105 <li>Bytecode compression with bzip2 has been implemented. All bytecode files
106 generated by LLVM will now be compressed by default. Compression can be
107 disabled with the <tt>-disable-compression</tt> option to the tools that can
108 generate bytecode files.
109 </li>
110 <li>A generic <a href="http://llvm.cs.uiuc.edu/PR353">compiler driver</a> and
111 an associated <a href="CommandGuide/html/llvm-ld.html">generic linker</a> have
112 been implemented. The compiler driver is generic because it can be configured
113 to pre-process, translate, optimize, assemble, and link code from any source
114 language. This aids compiler writers because all that is needed is a
115 source-to-bytecode or source-to-assembly translator and a configuration file.
116 The linker is generic because it allows dynamically loadable optimization
117 modules to be executed for link-time optimization. Language specific
118 link-time optimization modules can be created and executed automatically.
119 </li>
120 <li>The <a href="http://llvm.cs.uiuc.edu/PR263">dependent libraries</a>
121 feature has been implemented. This allows front end compilers to indicate in
122 the bytecode which libraries the bytecode needs to be linked with. Both the
123 C/C++ front end and Stacker support generating the required libraries. The
124 Linker now supports using this information to ensure required libaries are
125 linked into the module. This minimizes the need to use the <tt>-l</tt> option
126 when using <a href="CommandGuide/html/llvmc.html"><tt>llvmc</tt></a>
127 </li>
128 <li>The LLVM makefiles have been improved to build LLVM faster (2x) and
129 includes new targets (like dist-check, uninstall). One important change is
130 associated with <a href="http://llvm.cs.uiuc.edu/PR456">PR456</a>. The
131 libraries and tools will now be built into <tt>$builddir/Debug/{bin,lib}</tt>
132 instead of <tt>$builddir/tools/Debug</tt> and <tt>$builddir/lib/Debug</tt>.
133 Similarly for <tt>Release</tt> and <tt>Profile</tt> builds.
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]134 </li>
Chris Lattner7c8dd7f2004-11-17 18:19:32 +0000[diff] [blame]135 <li>The LLVM source code is much more compatible with Microsoft Visual C++,
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]136 including the JIT and runtime-code generation, though the entire system
137 may not work with it.
138 </li>
Chris Lattnere55cb542004-11-22 22:09:58 +0000[diff] [blame]139 <li>The target-to-JIT interfaces <a href="http://llvm.cs.uiuc.edu/PR283">are
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]140 now much simpler</a> and more powerful.
141 </li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]142</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]143
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]144</div>
145
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]146
147<!--=========================================================================-->
148<div class="doc_subsubsection">
149In this release, the following missing features were implemented:
150</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]151
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]152<div class="doc_text">
153
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]154<ol>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]155 <li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]156 arbitrary calls</a>
157 </li>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]158 <li>The <tt>llvm-ar</tt> tool was previously incomplete and didn't properly
159 support other ar(1) implementations. This has been corrected. <tt>llvm-ar</tt>
160 now fully supports all archive editing functions, table of contents listing,
161 extraction, and printing. It can also read BSD4.4/MacOSX and SVR4 style
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]162 archives. See <a href="CommandGuide/html/llvm-ar.html">llvm-ar</a> for
163 details.
164 </li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]165</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]166
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]167</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]168
169<!--=========================================================================-->
170<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]171<a name="qualityofimp">In this release, the following Quality of Implementation
172issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]173</div>
174
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]175<div class="doc_text">
176
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]177<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]178 <li><a href="http://llvm.cs.uiuc.edu/PR426">[llvmg++] Tons of warnings
179 are spewed when linking to libstdc++</a>
180 </li>
181 <li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
182 include/llvm/{Support,Config}</a>
183 </li>
Reid Spencerccbc9cf2004-11-22 18:40:51 +0000[diff] [blame]184 <li>The names of the libraries generated by compiling LLVM source have been
185 changed to ensure they do not conflict with other packages upon installation.
186 Each LLVM library is now prefixed with LLVM and uses mixed clase. For example,
187 the library <tt>libasmparser.a</tt> in 1.3 has become
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]188 <tt>libLLVMAsmParser.a</tt> in release 1.4.
189 </li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]190</ol>
191
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]192</div>
193
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]194<!--=========================================================================-->
195<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]196In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]197</div>
198
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]199<div class="doc_text">
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]200<ol>
Reid Spencer7409d1c2004-11-25 06:07:42 +0000[diff] [blame]201 <li><a href="http://llvm.cs.uiuc.edu/PR256">[autoconf] further standardizing
202 autoconf usage</a>. Various improvements in the configure.ac script were
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]203 made as well as the makefile system.
204 </li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]205</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]206</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]207
208<!--=========================================================================-->
209<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]210<a name="codequality">This release includes the following Code Quality
211improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]212</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]213
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]214<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]215<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]216 <li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
217 std::min/std::max</a>
218 </li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]219</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]220</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]221
222<!--=========================================================================-->
223<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]224<a name="bugfix">In this release, the following bugs in the previous release
225were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]226</div>
227
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]228<div class="doc_text">
229
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]230<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]231
232<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]233 <li><a href="http://llvm.cs.uiuc.edu/PR420">[licm] LICM invalidates alias
234 analysis info and uses broken information</a> (optimizer crash)</li>
235 <li><a href="http://llvm.cs.uiuc.edu/PR422">[asmwriter] Asmwriter is really
236 slow for functions with lots of values</a></li>
237 <li><a href="http://llvm.cs.uiuc.edu/PR423">[anders-aa] Andersen's AA is
238 completely broken in LLVM 1.3</a></li>
239 <li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction
240 tables defined</a></li>
241 <li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions
242 w/certain names tickles GNU 'as' bugs</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]243</ol>
244
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]245<p>Bugs in the C/C++ front-end:</p>
246
247<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]248 <li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are
249 instantiated</a></li>
250 <li><a href="http://llvm.cs.uiuc.edu/PR450">[llvmg++] Extern const globals
251 cannot be marked 'constant' if they have nontrivial ctors or dtors</a></li>
252 <li><a href="http://llvm.cs.uiuc.edu/PR461">[llvmgcc] Crash compiling unnamed
Chris Lattner4df69b82004-11-25 06:31:42 +0000[diff] [blame]253 bitfield which does not increase struct size</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]254</ol>
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]255
256<p>Bugs fixed in the Sparc V9 back-end:</p>
257
258<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]259 <li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]260 failure with certain indirect calls</a></li>
261</ol>
262
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]263</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]264
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]265<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]266<div class="doc_section">
267 <a name="portability">Portability and Supported Platforms</a>
268</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]269<!-- *********************************************************************** -->
270
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]271<div class="doc_text">
272
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]273<p>LLVM is known to work in the following platforms:</p>
274
275<ul>
276<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
277 other unix-like systems).</li>
278<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]279<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattner4f7ac4c2004-11-25 06:33:10 +0000[diff] [blame]280<li>PowerPC-based Mac OS X boxes, running 10.2 and above.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]281</ul>
282
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]283<p>The core LLVM infrastructure uses
284<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
285to the machine and operating system on which it is built. However, minor
286porting may be required to get LLVM to work on new platforms. We welcome your
287portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]288
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]289<p>Note that the LLVM build system does not currently support directories with
290spaces on them when running on Win32/cygwin. We strongly recommend running
291LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]292<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
293cygwin packages. By default, many important tools are not installed that
Chris Lattner5aff3552004-08-16 20:20:46 +0000[diff] [blame]294are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
295please make sure that there are no directories with spaces in them in your
296PATH environment variable.</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]297
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]298</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]299
300<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]301<div class="doc_section">
302 <a name="knownproblems">Known Problems</a>
303</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]304<!-- *********************************************************************** -->
305
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]306<div class="doc_text">
307
308<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]309component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]310sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]311href="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]312there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]313
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]314</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]315
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]316<!-- ======================================================================= -->
317<div class="doc_subsection">
318 <a name="experimental">Experimental features included with this release</a>
319</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]320
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]321<div class="doc_text">
322
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]323<p>The following components of this LLVM release are either untested, known to
324be broken or unreliable, or are in early development. These components should
325not be relied on, and bugs should not be filed against them, but they may be
326useful to some people. In particular, if you would like to work on one of these
327components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]328
329<ul>
330<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner9934f972004-09-14 16:43:13 +0000[diff] [blame]331 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]332<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
333 it should) and not thoroughly tested.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]334<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
335</ul>
336
337</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]338
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]339<!-- ======================================================================= -->
340<div class="doc_subsection">
341 <a name="core">Known problems with the LLVM Core</a>
342</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]343
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]344<div class="doc_text">
345
346<ul>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame^]347 <li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not work.
348 </li>
349 <li>The JIT does not use mutexes to protect its internal data structures. As
350 such, execution of a threaded program could cause these data structures to be
351 corrupted.
352 </li>
353 <li>Linking in static archive files (.a files) is slow by default because
354 there is no symbol table in the archive. To remedy this, run
355 <a href="CommandGuide/html/llvm-ranlib.html"><tt>llvm-ranlib</tt></a> on the
356 archive to add an LLVM symbol table.
357 </li>
358 <li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
359 objects/archives in the order specified on the command line.</a>
360 </li>
361 <li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not
362 mark values live across a setjmp as volatile</a>. This missing feature
363 only affects targets whose setjmp/longjmp libraries do not save and restore
364 the entire register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]365</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]366</div>
367
368<!-- ======================================================================= -->
369<div class="doc_subsection">
370 <a name="c-fe">Known problems with the C front-end</a>
371</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]372
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]373<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]374<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]375
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]376<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]377<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]378<li>C99 Variable sized arrays do not release stack memory when they go out of
379 scope. Thus, the following program may run out of stack space:
380<pre>
381 for (i = 0; i != 1000000; ++i) {
382 int X[n];
383 foo(X);
384 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]385</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]386
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]387<li>Initialization of global union variables can only be done <a
388href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
389member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]390
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]391<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
392external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]393
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]394</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]395</div>
396
397<!-- _______________________________________________________________________ -->
398<div class="doc_subsubsection">
399 Notes
400</div>
401
402<div class="doc_text">
403
404<ul>
405
406<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]407
408<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]409support for floating point data types of any size other than 32 and 64
410bits.</li>
411
412<li>The following Unix system functionality has not been tested and may not
413work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]414 <ol>
415 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
416 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
417 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
418 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
419 - These functions have not been tested.
420 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]421
422<li>Although many GCC extensions are supported, some are not. In particular,
423 the following extensions are known to <b>not be</b> supported:
424 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]425 <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]426 <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>
427 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
428 <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]429 <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]430 <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>
431 <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]432 <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>
433 <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>
434 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
435 <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]436 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]437
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]438 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]439 attribute means that the LLVM compiler ignores the presence of the attribute,
440 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]441 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]442 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]443
444 <ol>
445 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
446 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]447 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]448
449 <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]450
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]451 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]452 return.<br>
453
454 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
455 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
456 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
457
458 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
459 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
460 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
461
462 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
463 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
464 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]465
466 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
467 Specifying attributes of variables.<br>
468 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
469 <tt>deprecated</tt>, <tt>transparent_union</tt>,
470 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]471
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]472 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
473 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
474 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]475 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]476
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]477 <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]478 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]479 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]480
481 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
482 all target specific attributes.</li>
483
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]484 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
485 Other built-in functions.<br>
486 We support all builtins which have a C language equivalent (e.g.,
487 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
488 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]489 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
490 (currently ignored). We also support builtins for ISO C99 floating
491 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]492 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]493
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]494 <p>The following extensions <b>are</b> known to be supported:</p>
495
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]496 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]497 <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]498 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
499 <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]500 <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]501 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
502 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
503 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
504 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
505 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
506 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
507 <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>
508 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
509 <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]510 <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]511 <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]512 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
513or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]514 <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]515 <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]516 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
517 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
518 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
519 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
520 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
521 <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>
522 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
523 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
524 <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>
525 <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>
526 <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]527 <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]528 <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>
529 <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]530 </ol></li>
531
532</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]533
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]534<p>If you run into GCC extensions which have not been included in any of these
535lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]536
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]537</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]538
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]539<!-- ======================================================================= -->
540<div class="doc_subsection">
541 <a name="c++-fe">Known problems with the C++ front-end</a>
542</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]543
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]544<div class="doc_text">
545
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]546<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]547has not been tested as thoroughly as the C front-end. It has been tested and
548works for a number of non-trivial programs, but there may be lurking bugs.
549Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]550
551</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]552
553<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]554<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]555
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]556<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]557
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]558<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]559<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]560 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]561
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]562<li><b>IA-64 specific</b>: The C++ front-end does not use <a
563href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]564In particular, it just stores function pointers instead of function
565descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]566LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]567
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]568</ul>
569
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]570</div>
571
572<!-- _______________________________________________________________________ -->
573<div class="doc_subsubsection">
574 Notes
575</div>
576
577<div class="doc_text">
578
579<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]580
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]581<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
582parser is significantly more standards compliant (and picky) than prior GCC
583versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]584href="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]585
586<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]587 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]588 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]589 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]590 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]591
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]592<li>The LLVM C++ front-end follows the <a
593 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
594 This document, which is not Itanium specific, specifies a standard for name
595 mangling, class layout, v-table layout, RTTI formats, and other C++
596 representation issues. Because we use this API, code generated by the LLVM
597 compilers should be binary compatible with machine code generated by other
598 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
599 <i>However</i>, the exception handling mechanism used by LLVM is very
600 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]601 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]602
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]603</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]604
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]605</div>
606
607<!-- ======================================================================= -->
608<div class="doc_subsection">
609 <a name="x86-be">Known problems with the X86 back-end</a>
610</div>
611
612<div class="doc_text">
613
614<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]615 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]616</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]617
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]618</div>
619
620<!-- ======================================================================= -->
621<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]622 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]623</div>
624
625<div class="doc_text">
626
627<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]628<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
629several programs in the LLVM test suite</a></li>
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>
633
634<!-- ======================================================================= -->
635<div class="doc_subsection">
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]636 <a name="ppc-be">Known problems with the PowerPC back-end</a>
637</div>
638
639<div class="doc_text">
640
641<ul>
642<li>none yet</li>
643</ul>
644
645</div>
646
647<!-- ======================================================================= -->
648<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]649 <a name="c-be">Known problems with the C back-end</a>
650</div>
651
652<div class="doc_text">
653
654<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]655
656<li>The C back-end produces code that violates the ANSI C Type-Based Alias
657Analysis rules. As such, special options may be necessary to compile the code
658(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]659problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]660
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]661<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]662cannot include special floating point numbers like Not-A-Number or
663Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]664
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]665<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]666supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]667frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]668
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]669</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]670
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]671</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]672
673<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]674<div class="doc_section">
675 <a name="additionalinfo">Additional Information</a>
676</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]677<!-- *********************************************************************** -->
678
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]679<div class="doc_text">
680
681<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]682including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]683implemented in LLVM. The web page also contains versions of the API
684documentation which is up-to-date with the CVS version of the source code. You
685can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]686the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]687
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]688<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]689us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
690lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]691
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]692</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]693
694<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]695
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]696<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]697<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]698 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]699 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
700 <a href="http://validator.w3.org/check/referer"><img
701 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
702
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]703 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]704 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]705</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]706
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]707</body>
708</html>