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gerrit-public.fairphone.software / toolchain / llvm-project / 6caee97dc2820afaa2abaafb41f06eee21c2ad22 / . / llvm / docs / ReleaseNotes.html
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Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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4<head>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]7 <title>LLVM 1.4 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]10
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]11<div class="doc_title">LLVM 1.4 Release Notes</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]12
13<ol>
Misha Brukman80731b92003-11-22 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 Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]16 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]18 <li><a href="#knownproblems">Known Problems</a>
19 <ul>
Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]20 <li><a href="#experimental">Experimental features included in this
21 release</a>
Chris Lattner3d482502003-10-02 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 Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]26 <li><a href="#sparcv9-be">Known problems with the SparcV9 Back-end</a>
Chris Lattnerdf925ce2004-11-07 01:55:32 +0000[diff] [blame]27 <li><a href="#ppc-be">Known problems with the PowerPC Back-end</a>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]28 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]29 </ul></li>
30 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]31</ol>
32
Chris Lattner020e1fc2004-05-23 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]35</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]36
37<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]38<div class="doc_section">
39 <a name="intro">Introduction</a>
40</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]41<!-- *********************************************************************** -->
42
Misha Brukman80731b92003-11-22 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 Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]46infrastructure, release 1.4. Here we describe the status of LLVM, including any
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]47known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]48version of this document can be found on the <a
Chris Lattner163c3262004-08-16 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 Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]50not reading this on the LLVM web pages, you should probably go there because
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]51this document may be updated after the release.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]52
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]53<p>For more information about LLVM, including information about potentially more
Chris Lattnere7525b52003-10-07 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]57list</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]58
Chris Lattnere76e9ab2003-12-12 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]62href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
63
64</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]65
66<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]67<div class="doc_section">
68 <a name="whatsnew">What's New?</a>
69</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]70<!-- *********************************************************************** -->
71
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]72<div class="doc_text">
73
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]74<p>This is the fifth public release of the LLVM compiler infrastructure.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]75
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]76<p> At this time, LLVM is known to correctly compile and run all C &amp; C++
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]77SPEC CPU95 &amp; 2000 benchmarks, the Olden benchmarks, and the Ptrdist
Chris Lattner55266332004-10-16 18:35:57 +0000[diff] [blame]78benchmarks, and <b>many</b> other C and C++ programs.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]79
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]80</div>
81
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]82<!--=========================================================================-->
83<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]84<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]85</div>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]86
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]87<div class="doc_text">
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]88<ol>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]89 <li>LLVM now optimizes global variables significantly more than it did
90 before.
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]91 </li>
Reid Spencer493d9c22004-11-25 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 Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]134 </li>
Chris Lattnerd5f52882004-11-17 18:19:32 +0000[diff] [blame]135 <li>The LLVM source code is much more compatible with Microsoft Visual C++,
Reid Spencer493d9c22004-11-25 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 Lattnerb7696902004-11-22 22:09:58 +0000[diff] [blame]139 <li>The target-to-JIT interfaces <a href="http://llvm.cs.uiuc.edu/PR283">are
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]140 now much simpler</a> and more powerful.
141 </li>
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]142</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]143
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]144</div>
145
Chris Lattnerba7bd472003-12-06 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 Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]151
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]152<div class="doc_text">
153
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]154<ol>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]155 <li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]156 arbitrary calls</a>
157 </li>
Reid Spencere4190fa2004-11-18 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 Spencer493d9c22004-11-25 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]165</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]166
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]167</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]168
169<!--=========================================================================-->
170<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]171<a name="qualityofimp">In this release, the following Quality of Implementation
172issues were fixed:</a>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]173</div>
174
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]175<div class="doc_text">
176
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]177<ol>
Reid Spencer493d9c22004-11-25 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 Spencerb4e3ec82004-11-22 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 Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]188 <tt>libLLVMAsmParser.a</tt> in release 1.4.
189 </li>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]190</ol>
191
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]192</div>
193
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]194<!--=========================================================================-->
195<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]196In this release, the following build problems were fixed:
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]197</div>
198
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]199<div class="doc_text">
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]200<ol>
Reid Spencer26864642004-11-25 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 Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]203 made as well as the makefile system.
204 </li>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]205</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]206</div>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]207
208<!--=========================================================================-->
209<div class="doc_subsubsection">
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]210<a name="codequality">This release includes the following Code Quality
211improvements:</a>
Chris Lattner23257062004-05-23 20:42:08 +0000[diff] [blame]212</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]213
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]214<div class="doc_text">
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]215<ol>
Reid Spencer493d9c22004-11-25 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]219</ol>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]220</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]221
222<!--=========================================================================-->
223<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]224<a name="bugfix">In this release, the following bugs in the previous release
225were fixed:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]226</div>
227
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]228<div class="doc_text">
229
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]230<p>Bugs fixed in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]231
232<ol>
Reid Spencer493d9c22004-11-25 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 Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]243</ol>
244
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]245<p>Bugs in the C/C++ front-end:</p>
246
247<ol>
Reid Spencer493d9c22004-11-25 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 Lattner6345ee292004-11-25 06:31:42 +0000[diff] [blame]253 bitfield which does not increase struct size</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]254</ol>
Brian Gaeke730d8d62004-08-24 07:43:48 +0000[diff] [blame]255
256<p>Bugs fixed in the Sparc V9 back-end:</p>
257
258<ol>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]259 <li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaeke730d8d62004-08-24 07:43:48 +0000[diff] [blame]260 failure with certain indirect calls</a></li>
261</ol>
262
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]263</div>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]264
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]265<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]266<div class="doc_section">
267 <a name="portability">Portability and Supported Platforms</a>
268</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]269<!-- *********************************************************************** -->
270
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]271<div class="doc_text">
272
Chris Lattner2c7b0872004-06-01 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 Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]279<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnerd0af8e22004-11-25 06:33:10 +0000[diff] [blame]280<li>PowerPC-based Mac OS X boxes, running 10.2 and above.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]281</ul>
282
Brian Gaekee3e557e2004-05-09 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]288
Chris Lattner2c7b0872004-06-01 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 Lattnerce1a3842004-06-01 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 Lattnera752fce2004-08-16 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 Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]297
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]298</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]299
300<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]301<div class="doc_section">
302 <a name="knownproblems">Known Problems</a>
303</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]304<!-- *********************************************************************** -->
305
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]309component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]310sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]311href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]312there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]313
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]314</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]315
Chris Lattnerb911de42004-03-14 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]320
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]321<div class="doc_text">
322
Misha Brukmanfa50a222004-05-12 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 Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]328
329<ul>
330<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner09f3ac92004-09-14 16:43:13 +0000[diff] [blame]331 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerb911de42004-03-14 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 Lattnerb911de42004-03-14 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]338
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]343
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]344<div class="doc_text">
345
346<ul>
Reid Spencer493d9c22004-11-25 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>
Reid Spencer6caee972004-11-25 22:43:58 +0000[diff] [blame^]365 <li><a href="http://llvm.cs.uiuc.edu/PR427">[bytecode] Assertion on V1
366 Bytecode Files</a>. This bug won't be fixed because V1 bytecode had its own
367 problems, no one is using V1 bytecode any more, and the fix is non-trivial.
368 </li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]369</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]370</div>
371
372<!-- ======================================================================= -->
373<div class="doc_subsection">
374 <a name="c-fe">Known problems with the C front-end</a>
375</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]376
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]377<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]378<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]379
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]380<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]381<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]382<li>C99 Variable sized arrays do not release stack memory when they go out of
383 scope. Thus, the following program may run out of stack space:
384<pre>
385 for (i = 0; i != 1000000; ++i) {
386 int X[n];
387 foo(X);
388 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]389</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]390
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]391<li>Initialization of global union variables can only be done <a
392href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
393member</a>.</li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]394
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]395<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
396external function is re-declared as static</a></li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]397
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]398</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]399</div>
400
401<!-- _______________________________________________________________________ -->
402<div class="doc_subsubsection">
403 Notes
404</div>
405
406<div class="doc_text">
407
408<ul>
409
410<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]411
412<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]413support for floating point data types of any size other than 32 and 64
414bits.</li>
415
416<li>The following Unix system functionality has not been tested and may not
417work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]418 <ol>
419 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
420 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
421 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
422 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
423 - These functions have not been tested.
424 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]425
426<li>Although many GCC extensions are supported, some are not. In particular,
427 the following extensions are known to <b>not be</b> supported:
428 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]429 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]430 <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>
431 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
432 <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 Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]433 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]434 <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>
435 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]436 <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>
437 <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>
438 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
439 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li>
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]440 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]441
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]442 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]443 attribute means that the LLVM compiler ignores the presence of the attribute,
444 but the code should still work. An unsupported attribute is one which is
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]445 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]446 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]447
448 <ol>
449 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
450 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]451 Supported, but allocated stack space is not freed until the function returns (noted above).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]452
453 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>:
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]454
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]455 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]456 return.<br>
457
458 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
459 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
460 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
461
462 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
463 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
464 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
465
466 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
467 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
468 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]469
470 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
471 Specifying attributes of variables.<br>
472 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
473 <tt>deprecated</tt>, <tt>transparent_union</tt>,
474 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]475
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]476 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
477 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
478 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]479 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]480
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]481 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.<br>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]482 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]483 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]484
485 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
486 all target specific attributes.</li>
487
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]488 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
489 Other built-in functions.<br>
490 We support all builtins which have a C language equivalent (e.g.,
491 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
492 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerb7c4bac2004-06-18 06:26:29 +0000[diff] [blame]493 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
494 (currently ignored). We also support builtins for ISO C99 floating
495 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]496 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]497
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]498 <p>The following extensions <b>are</b> known to be supported:</p>
499
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]500 <ol>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]501 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]502 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
503 <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 Lattnerce33a1b2004-06-22 03:48:17 +0000[diff] [blame]504 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]505 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
506 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
507 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
508 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
509 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
510 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
511 <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>
512 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
513 <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 Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]514 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]515 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]516 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
517or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]518 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]519 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]520 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
521 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
522 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
523 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
524 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
525 <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>
526 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
527 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
528 <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>
529 <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>
530 <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 Lattner3646dad2004-02-14 04:08:29 +0000[diff] [blame]531 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]532 <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>
533 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute%20Syntax">Attribute Syntax</a>: Formal syntax for attributes.</li>
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]534 </ol></li>
535
536</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]537
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]538<p>If you run into GCC extensions which have not been included in any of these
539lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]540
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]541</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]542
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]543<!-- ======================================================================= -->
544<div class="doc_subsection">
545 <a name="c++-fe">Known problems with the C++ front-end</a>
546</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]547
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]548<div class="doc_text">
549
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]550<p>For this release, the C++ front-end is considered to be fully functional but
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]551has not been tested as thoroughly as the C front-end. It has been tested and
552works for a number of non-trivial programs, but there may be lurking bugs.
553Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]554
555</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]556
557<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]558<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]559
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]560<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]561
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]562<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]563<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]564 front-end</a>.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]565
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]566<li><b>IA-64 specific</b>: The C++ front-end does not use <a
567href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]568In particular, it just stores function pointers instead of function
569descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner2fd93492004-08-02 20:29:51 +0000[diff] [blame]570LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]571
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]572</ul>
573
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]574</div>
575
576<!-- _______________________________________________________________________ -->
577<div class="doc_subsubsection">
578 Notes
579</div>
580
581<div class="doc_text">
582
583<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]584
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]585<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
586parser is significantly more standards compliant (and picky) than prior GCC
587versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]588href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]589
590<li>Destructors for local objects are not always run when a <tt>longjmp</tt> is
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]591 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]592 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]593 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]594 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]595
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]596<li>The LLVM C++ front-end follows the <a
597 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
598 This document, which is not Itanium specific, specifies a standard for name
599 mangling, class layout, v-table layout, RTTI formats, and other C++
600 representation issues. Because we use this API, code generated by the LLVM
601 compilers should be binary compatible with machine code generated by other
602 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
603 <i>However</i>, the exception handling mechanism used by LLVM is very
604 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]605 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]606
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]607</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]608
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]609</div>
610
611<!-- ======================================================================= -->
612<div class="doc_subsection">
613 <a name="x86-be">Known problems with the X86 back-end</a>
614</div>
615
616<div class="doc_text">
617
618<ul>
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]619 <li>none yet</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]620</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]621
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]622</div>
623
624<!-- ======================================================================= -->
625<div class="doc_subsection">
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]626 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]627</div>
628
629<div class="doc_text">
630
631<ul>
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]632<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
633several programs in the LLVM test suite</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]634</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]635
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]636</div>
637
638<!-- ======================================================================= -->
639<div class="doc_subsection">
Chris Lattnerdf925ce2004-11-07 01:55:32 +0000[diff] [blame]640 <a name="ppc-be">Known problems with the PowerPC back-end</a>
641</div>
642
643<div class="doc_text">
644
645<ul>
646<li>none yet</li>
647</ul>
648
649</div>
650
651<!-- ======================================================================= -->
652<div class="doc_subsection">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]653 <a name="c-be">Known problems with the C back-end</a>
654</div>
655
656<div class="doc_text">
657
658<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]659
660<li>The C back-end produces code that violates the ANSI C Type-Based Alias
661Analysis rules. As such, special options may be necessary to compile the code
662(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]663problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]664
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]665<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]666cannot include special floating point numbers like Not-A-Number or
667Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]668
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]669<li><a href="http://llvm.cs.uiuc.edu/PR56">Zero arg vararg functions are not
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]670supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]671frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]672
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]673</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]674
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]675</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]676
677<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]678<div class="doc_section">
679 <a name="additionalinfo">Additional Information</a>
680</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]681<!-- *********************************************************************** -->
682
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]683<div class="doc_text">
684
685<p>A wide variety of additional information is available on the LLVM web page,
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]686including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]687implemented in LLVM. The web page also contains versions of the API
688documentation which is up-to-date with the CVS version of the source code. You
689can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]690the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]691
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]692<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]693us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
694lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]695
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]696</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]697
698<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]699
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]700<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]701<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]702 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]703 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
704 <a href="http://validator.w3.org/check/referer"><img
705 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
706
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]707 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]708 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]709</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]710
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]711</body>
712</html>