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gerrit-public.fairphone.software / toolchain / llvm-project / 26864643788593125d5975185c9a918d52d1c3e8 / . / 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">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]6 <link rel="stylesheet" href="llvm.css" type="text/css">
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">
88
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]89<ol>
Misha Brukmanbbd150e2004-10-16 19:13:58 +0000[diff] [blame]90 <li>The test/Programs hierarchy <a href="http://llvm.cs.uiuc.edu/PR257">has
Chris Lattner55266332004-10-16 18:35:57 +0000[diff] [blame]91 been moved out of the main LLVM tree</a> into a separate CVS repo and
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]92 tarball. This shrinks the distribution size of LLVM itself dramatically.
93 </li>
Chris Lattner55266332004-10-16 18:35:57 +0000[diff] [blame]94 <li>LLVM now optimizes global variables significantly more than it did
95 before.</li>
96 <li>LLVM now includes the new '<tt>undef</tt>' value and <a
97 href="LangRef.html#i_unreachable"><tt>unreachable</tt></a> instruction,
98 which give the optimizer more information about the behavior of the
99 program.</li>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]100 <li>The LLVM makefiles have been improved to build LLVM much faster (2x) and
101 includes new targets (like dist-check, uninstall). One important change is
102 associated with <a href="http://llvm.cs.uiuc.edu/PR456>PR456">PR456</a>.
103 The libraries and tools will now be built into
104 <tt>$builddir/Debug/{bin,lib}</tt> instead of
105 <tt>$builddir/tools/Debug</tt> and <tt>$builddir/lib/Debug</tt>. Similarly
106 for <tt>Release</tt> and <tt>Profile</tt> builds.
107 </li>
Chris Lattnerd5f52882004-11-17 18:19:32 +0000[diff] [blame]108 <li>The LLVM source code is much more compatible with Microsoft Visual C++,
109 including the JIT and runtime-code generation, though the entire system
110 may not work with it.</li>
Chris Lattner24874312004-11-18 21:25:11 +0000[diff] [blame]111 <li>llvmgcc and llvmg++ now emit source line number information when '-g' is
112 passed in. This information can be used with llvm-db or other tools and
113 passes.</li>
Chris Lattnerb7696902004-11-22 22:09:58 +0000[diff] [blame]114 <li>The target-to-JIT interfaces <a href="http://llvm.cs.uiuc.edu/PR283">are
115 now much simpler</a> and more powerful.</li>
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]116</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]117
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]118</div>
119
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]120
121<!--=========================================================================-->
122<div class="doc_subsubsection">
123In this release, the following missing features were implemented:
124</div>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]125
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]126<div class="doc_text">
127
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]128<ol>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]129 <li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
Misha Brukmanbbd150e2004-10-16 19:13:58 +0000[diff] [blame]130 arbitrary calls</a></li>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]131 <li>The <tt>llvm-ar</tt> tool was previously incomplete and didn't properly
132 support other ar(1) implementations. This has been corrected. <tt>llvm-ar</tt>
133 now fully supports all archive editing functions, table of contents listing,
134 extraction, and printing. It can also read BSD4.4/MacOSX and SVR4 style
135 archives. See <a
136 href="http://llvm.cs.uiuc.edu/docs/CommandGuide/html/llvm-ar.html">llvm-ar</a>
137 for details.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]138</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]139
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]140</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]141
142<!--=========================================================================-->
143<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]144<a name="qualityofimp">In this release, the following Quality of Implementation
145issues were fixed:</a>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]146</div>
147
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]148<div class="doc_text">
149
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]150<ol>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]151<li><a href="http://llvm.cs.uiuc.edu/PR426">[llvmg++] Tons of warnings are spewed when
Chris Lattner615ffb82004-08-20 00:36:23 +0000[diff] [blame]152 linking to libstdc++</a></li>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]153<li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
Chris Lattner2249dd12004-09-19 19:21:26 +0000[diff] [blame]154 include/llvm/{Support,Config}</a></li>
Reid Spencerb4e3ec82004-11-22 18:40:51 +0000[diff] [blame]155 <li>The names of the libraries generated by compiling LLVM source have been
156 changed to ensure they do not conflict with other packages upon installation.
157 Each LLVM library is now prefixed with LLVM and uses mixed clase. For example,
158 the library <tt>libasmparser.a</tt> in 1.3 has become
159 <tt>libLLVMAsmParser.a</tt> in release 1.4.</li>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]160</ol>
161
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]162</div>
163
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]164<!--=========================================================================-->
165<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]166In this release, the following build problems were fixed:
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]167</div>
168
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]169<div class="doc_text">
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]170<ol>
Reid Spencer26864642004-11-25 06:07:42 +0000[diff] [blame^]171 <li><a href="http://llvm.cs.uiuc.edu/PR256">[autoconf] further standardizing
172 autoconf usage</a>. Various improvements in the configure.ac script were
173 made as well as the makefile system.</li>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]174</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]175</div>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]176
177<!--=========================================================================-->
178<div class="doc_subsubsection">
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]179<a name="codequality">This release includes the following Code Quality
180improvements:</a>
Chris Lattner23257062004-05-23 20:42:08 +0000[diff] [blame]181</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]182
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]183<div class="doc_text">
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]184<ol>
Chris Lattnerb84e1c52004-10-09 19:37:02 +0000[diff] [blame]185<li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
Chris Lattner2249dd12004-09-19 19:21:26 +0000[diff] [blame]186 std::min/std::max</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]187</ol>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]188</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]189
190<!--=========================================================================-->
191<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]192<a name="bugfix">In this release, the following bugs in the previous release
193were fixed:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]194</div>
195
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]196<div class="doc_text">
197
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]198<p>Bugs fixed in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]199
200<ol>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]201<li><a href="http://llvm.cs.uiuc.edu/PR420">[licm] LICM invalidates alias analysis info
Chris Lattner59d448f2004-09-15 01:09:25 +0000[diff] [blame]202 and uses broken information</a> (optimizer crash)</li>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]203<li><a href="http://llvm.cs.uiuc.edu/PR422">[asmwriter] Asmwriter is really slow for
Chris Lattner59d448f2004-09-15 01:09:25 +0000[diff] [blame]204 functions with lots of values</a></li>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]205<li><a href="http://llvm.cs.uiuc.edu/PR423">[anders-aa] Andersen's AA is completely
Chris Lattnera10ed3b2004-08-16 05:46:57 +0000[diff] [blame]206 broken in LLVM 1.3</a></li>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]207<li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction tables
Reid Spencer7d0a1232004-08-27 00:48:26 +0000[diff] [blame]208 defined</a></li>
Chris Lattnerbff64722004-10-25 22:13:02 +0000[diff] [blame]209<li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions w/certain
210 names tickles GNU 'as' bugs</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]211</ol>
212
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]213<p>Bugs in the C/C++ front-end:</p>
214
215<ol>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]216<li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are instantiated</a></li>
217<li><a href="http://llvm.cs.uiuc.edu/PR450">[llvmg++] Extern const globals cannot be
Chris Lattner2426ff92004-10-05 00:23:02 +0000[diff] [blame]218marked 'constant' if they have nontrivial ctors or dtors</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]219</ol>
Brian Gaeke730d8d62004-08-24 07:43:48 +0000[diff] [blame]220
221<p>Bugs fixed in the Sparc V9 back-end:</p>
222
223<ol>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]224<li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaeke730d8d62004-08-24 07:43:48 +0000[diff] [blame]225 failure with certain indirect calls</a></li>
226</ol>
227
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]228</div>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]229
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]230<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]231<div class="doc_section">
232 <a name="portability">Portability and Supported Platforms</a>
233</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]234<!-- *********************************************************************** -->
235
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]236<div class="doc_text">
237
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]238<p>LLVM is known to work in the following platforms:</p>
239
240<ul>
241<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
242 other unix-like systems).</li>
243<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]244<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnerd21e3d02004-08-05 21:53:13 +0000[diff] [blame]245<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
246support is available yet, and LLC support is beta. The C backend can be used
247to produce stable code for this platform.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]248</ul>
249
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]250<p>The core LLVM infrastructure uses
251<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
252to the machine and operating system on which it is built. However, minor
253porting may be required to get LLVM to work on new platforms. We welcome your
254portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]255
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]256<p>Note that the LLVM build system does not currently support directories with
257spaces on them when running on Win32/cygwin. We strongly recommend running
258LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattnerce1a3842004-06-01 19:41:30 +0000[diff] [blame]259<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
260cygwin packages. By default, many important tools are not installed that
Chris Lattnera752fce2004-08-16 20:20:46 +0000[diff] [blame]261are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
262please make sure that there are no directories with spaces in them in your
263PATH environment variable.</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]264
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]265</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]266
267<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]268<div class="doc_section">
269 <a name="knownproblems">Known Problems</a>
270</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]271<!-- *********************************************************************** -->
272
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]273<div class="doc_text">
274
275<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]276component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]277sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]278href="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]279there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]280
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]281</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]282
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]283<!-- ======================================================================= -->
284<div class="doc_subsection">
285 <a name="experimental">Experimental features included with this release</a>
286</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]287
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]288<div class="doc_text">
289
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]290<p>The following components of this LLVM release are either untested, known to
291be broken or unreliable, or are in early development. These components should
292not be relied on, and bugs should not be filed against them, but they may be
293useful to some people. In particular, if you would like to work on one of these
294components, please contact us on the llvmdev list.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]295
296<ul>
Misha Brukman467ea6b2004-08-05 21:04:03 +0000[diff] [blame]297<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
298benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
299details.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]300<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner09f3ac92004-09-14 16:43:13 +0000[diff] [blame]301 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]302<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
303 it should) and not thoroughly tested.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]304<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
305</ul>
306
307</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]308
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]309<!-- ======================================================================= -->
310<div class="doc_subsection">
311 <a name="core">Known problems with the LLVM Core</a>
312</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]313
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]314<div class="doc_text">
315
316<ul>
317
318<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
319work.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]320
321<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]322such, execution of a threaded program could cause these data structures to be
323corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]324
Chris Lattnerc0171082004-08-08 03:33:07 +0000[diff] [blame]325<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]326table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]327
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]328<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
329objects/archives in the order specified on the command line.</a></li>
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]330
331<li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not mark
John Criswell5d6345a2004-03-12 21:29:42 +0000[diff] [blame]332values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]333targets whose setjmp/longjmp libraries do not save and restore the entire
334register file.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]335</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]336</div>
337
338<!-- ======================================================================= -->
339<div class="doc_subsection">
340 <a name="c-fe">Known problems with the C front-end</a>
341</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]342
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]343<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]344<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]345
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]346<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]347<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]348<li>C99 Variable sized arrays do not release stack memory when they go out of
349 scope. Thus, the following program may run out of stack space:
350<pre>
351 for (i = 0; i != 1000000; ++i) {
352 int X[n];
353 foo(X);
354 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]355</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]356
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]357<li>Initialization of global union variables can only be done <a
358href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
359member</a>.</li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]360
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]361<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
362external function is re-declared as static</a></li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]363
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]364</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]365</div>
366
367<!-- _______________________________________________________________________ -->
368<div class="doc_subsubsection">
369 Notes
370</div>
371
372<div class="doc_text">
373
374<ul>
375
376<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]377
378<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]379support for floating point data types of any size other than 32 and 64
380bits.</li>
381
382<li>The following Unix system functionality has not been tested and may not
383work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]384 <ol>
385 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
386 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
387 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
388 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
389 - These functions have not been tested.
390 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]391
392<li>Although many GCC extensions are supported, some are not. In particular,
393 the following extensions are known to <b>not be</b> supported:
394 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]395 <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]396 <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>
397 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
398 <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]399 <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]400 <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>
401 <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]402 <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>
403 <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>
404 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
405 <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]406 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]407
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]408 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]409 attribute means that the LLVM compiler ignores the presence of the attribute,
410 but the code should still work. An unsupported attribute is one which is
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]411 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]412 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]413
414 <ol>
415 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
416 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]417 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]418
419 <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]420
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]421 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]422 return.<br>
423
424 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
425 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
426 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
427
428 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
429 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
430 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
431
432 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
433 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
434 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]435
436 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
437 Specifying attributes of variables.<br>
438 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
439 <tt>deprecated</tt>, <tt>transparent_union</tt>,
440 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]441
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]442 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
443 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
444 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]445 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]446
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]447 <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]448 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]449 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]450
451 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
452 all target specific attributes.</li>
453
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]454 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
455 Other built-in functions.<br>
456 We support all builtins which have a C language equivalent (e.g.,
457 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
458 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerb7c4bac2004-06-18 06:26:29 +0000[diff] [blame]459 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
460 (currently ignored). We also support builtins for ISO C99 floating
461 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]462 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]463
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]464 <p>The following extensions <b>are</b> known to be supported:</p>
465
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]466 <ol>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]467 <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]468 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
469 <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]470 <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]471 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
472 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
473 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
474 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
475 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
476 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
477 <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>
478 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
479 <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]480 <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]481 <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]482 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
483or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]484 <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]485 <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]486 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
487 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
488 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
489 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
490 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
491 <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>
492 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
493 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
494 <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>
495 <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>
496 <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]497 <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]498 <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>
499 <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]500 </ol></li>
501
502</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]503
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]504<p>If you run into GCC extensions which have not been included in any of these
505lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]506
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]507</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]508
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]509<!-- ======================================================================= -->
510<div class="doc_subsection">
511 <a name="c++-fe">Known problems with the C++ front-end</a>
512</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]513
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]514<div class="doc_text">
515
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]516<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]517has not been tested as thoroughly as the C front-end. It has been tested and
518works for a number of non-trivial programs, but there may be lurking bugs.
519Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]520
521</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]522
523<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]524<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]525
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]526<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]527
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]528<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]529<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]530 front-end</a>.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]531
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]532<li><b>IA-64 specific</b>: The C++ front-end does not use <a
533href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]534In particular, it just stores function pointers instead of function
535descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner2fd93492004-08-02 20:29:51 +0000[diff] [blame]536LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]537
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]538</ul>
539
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]540</div>
541
542<!-- _______________________________________________________________________ -->
543<div class="doc_subsubsection">
544 Notes
545</div>
546
547<div class="doc_text">
548
549<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]550
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]551<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
552parser is significantly more standards compliant (and picky) than prior GCC
553versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]554href="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]555
556<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]557 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]558 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]559 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]560 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]561
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]562<li>The LLVM C++ front-end follows the <a
563 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
564 This document, which is not Itanium specific, specifies a standard for name
565 mangling, class layout, v-table layout, RTTI formats, and other C++
566 representation issues. Because we use this API, code generated by the LLVM
567 compilers should be binary compatible with machine code generated by other
568 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
569 <i>However</i>, the exception handling mechanism used by LLVM is very
570 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]571 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]572
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]573</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]574
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]575</div>
576
577<!-- ======================================================================= -->
578<div class="doc_subsection">
579 <a name="x86-be">Known problems with the X86 back-end</a>
580</div>
581
582<div class="doc_text">
583
584<ul>
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]585 <li>none yet</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]586</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]587
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]588</div>
589
590<!-- ======================================================================= -->
591<div class="doc_subsection">
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]592 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]593</div>
594
595<div class="doc_text">
596
597<ul>
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]598<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
599several programs in the LLVM test suite</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]600</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]601
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]602</div>
603
604<!-- ======================================================================= -->
605<div class="doc_subsection">
Chris Lattnerdf925ce2004-11-07 01:55:32 +0000[diff] [blame]606 <a name="ppc-be">Known problems with the PowerPC back-end</a>
607</div>
608
609<div class="doc_text">
610
611<ul>
612<li>none yet</li>
613</ul>
614
615</div>
616
617<!-- ======================================================================= -->
618<div class="doc_subsection">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]619 <a name="c-be">Known problems with the C back-end</a>
620</div>
621
622<div class="doc_text">
623
624<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]625
626<li>The C back-end produces code that violates the ANSI C Type-Based Alias
627Analysis rules. As such, special options may be necessary to compile the code
628(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]629problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]630
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]631<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]632cannot include special floating point numbers like Not-A-Number or
633Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]634
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]635<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]636supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]637frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]638
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]639</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]640
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]641</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]642
643<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]644<div class="doc_section">
645 <a name="additionalinfo">Additional Information</a>
646</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]647<!-- *********************************************************************** -->
648
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]649<div class="doc_text">
650
651<p>A wide variety of additional information is available on the LLVM web page,
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]652including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]653implemented in LLVM. The web page also contains versions of the API
654documentation which is up-to-date with the CVS version of the source code. You
655can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]656the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]657
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]658<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]659us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
660lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]661
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]662</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]663
664<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]665
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]666<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]667<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]668 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]669 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
670 <a href="http://validator.w3.org/check/referer"><img
671 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
672
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]673 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]674 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]675</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]676
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]677</body>
678</html>