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gerrit-public.fairphone.software / toolchain / llvm-project / c5753055eab2bcb0d46a3063d7e3a7809c2ce197 / . / llvm / docs / ReleaseNotes.html
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4<head>
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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">
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 Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]114</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]115
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]116</div>
117
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]118
119<!--=========================================================================-->
120<div class="doc_subsubsection">
121In this release, the following missing features were implemented:
122</div>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]123
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]124<div class="doc_text">
125
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]126<ol>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]127 <li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
Misha Brukmanbbd150e2004-10-16 19:13:58 +0000[diff] [blame]128 arbitrary calls</a></li>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]129 <li>The <tt>llvm-ar</tt> tool was previously incomplete and didn't properly
130 support other ar(1) implementations. This has been corrected. <tt>llvm-ar</tt>
131 now fully supports all archive editing functions, table of contents listing,
132 extraction, and printing. It can also read BSD4.4/MacOSX and SVR4 style
133 archives. See <a
134 href="http://llvm.cs.uiuc.edu/docs/CommandGuide/html/llvm-ar.html">llvm-ar</a>
135 for details.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]136</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]137
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]138</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]139
140<!--=========================================================================-->
141<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]142<a name="qualityofimp">In this release, the following Quality of Implementation
143issues were fixed:</a>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]144</div>
145
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]146<div class="doc_text">
147
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]148<ol>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]149<li><a href="http://llvm.cs.uiuc.edu/PR426">[llvmg++] Tons of warnings are spewed when
Chris Lattner615ffb82004-08-20 00:36:23 +0000[diff] [blame]150 linking to libstdc++</a></li>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]151<li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
Chris Lattner2249dd12004-09-19 19:21:26 +0000[diff] [blame]152 include/llvm/{Support,Config}</a></li>
Reid Spencerb4e3ec82004-11-22 18:40:51 +0000[diff] [blame]153 <li>The names of the libraries generated by compiling LLVM source have been
154 changed to ensure they do not conflict with other packages upon installation.
155 Each LLVM library is now prefixed with LLVM and uses mixed clase. For example,
156 the library <tt>libasmparser.a</tt> in 1.3 has become
157 <tt>libLLVMAsmParser.a</tt> in release 1.4.</li>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]158</ol>
159
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]160</div>
161
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]162<!--=========================================================================-->
163<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]164In this release, the following build problems were fixed:
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]165</div>
166
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]167<div class="doc_text">
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]168<ol>
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]169<li></li>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]170</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]171</div>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]172
173<!--=========================================================================-->
174<div class="doc_subsubsection">
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]175<a name="codequality">This release includes the following Code Quality
176improvements:</a>
Chris Lattner23257062004-05-23 20:42:08 +0000[diff] [blame]177</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]178
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]179<div class="doc_text">
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]180<ol>
Chris Lattnerb84e1c52004-10-09 19:37:02 +0000[diff] [blame]181<li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
Chris Lattner2249dd12004-09-19 19:21:26 +0000[diff] [blame]182 std::min/std::max</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]183</ol>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]184</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]185
186<!--=========================================================================-->
187<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]188<a name="bugfix">In this release, the following bugs in the previous release
189were fixed:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]190</div>
191
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]192<div class="doc_text">
193
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]194<p>Bugs fixed in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]195
196<ol>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]197<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]198 and uses broken information</a> (optimizer crash)</li>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]199<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]200 functions with lots of values</a></li>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]201<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]202 broken in LLVM 1.3</a></li>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]203<li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction tables
Reid Spencer7d0a1232004-08-27 00:48:26 +0000[diff] [blame]204 defined</a></li>
Chris Lattnerbff64722004-10-25 22:13:02 +0000[diff] [blame]205<li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions w/certain
206 names tickles GNU 'as' bugs</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]207</ol>
208
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]209<p>Bugs in the C/C++ front-end:</p>
210
211<ol>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]212<li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are instantiated</a></li>
213<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]214marked 'constant' if they have nontrivial ctors or dtors</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]215</ol>
Brian Gaeke730d8d62004-08-24 07:43:48 +0000[diff] [blame]216
217<p>Bugs fixed in the Sparc V9 back-end:</p>
218
219<ol>
Chris Lattner99e41112004-10-09 19:19:57 +0000[diff] [blame]220<li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaeke730d8d62004-08-24 07:43:48 +0000[diff] [blame]221 failure with certain indirect calls</a></li>
222</ol>
223
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]224</div>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]225
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]226<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]227<div class="doc_section">
228 <a name="portability">Portability and Supported Platforms</a>
229</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]230<!-- *********************************************************************** -->
231
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]232<div class="doc_text">
233
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]234<p>LLVM is known to work in the following platforms:</p>
235
236<ul>
237<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
238 other unix-like systems).</li>
239<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]240<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnerd21e3d02004-08-05 21:53:13 +0000[diff] [blame]241<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
242support is available yet, and LLC support is beta. The C backend can be used
243to produce stable code for this platform.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]244</ul>
245
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]246<p>The core LLVM infrastructure uses
247<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
248to the machine and operating system on which it is built. However, minor
249porting may be required to get LLVM to work on new platforms. We welcome your
250portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]251
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]252<p>Note that the LLVM build system does not currently support directories with
253spaces on them when running on Win32/cygwin. We strongly recommend running
254LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattnerce1a3842004-06-01 19:41:30 +0000[diff] [blame]255<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
256cygwin packages. By default, many important tools are not installed that
Chris Lattnera752fce2004-08-16 20:20:46 +0000[diff] [blame]257are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
258please make sure that there are no directories with spaces in them in your
259PATH environment variable.</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]260
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]261</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]262
263<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]264<div class="doc_section">
265 <a name="knownproblems">Known Problems</a>
266</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]267<!-- *********************************************************************** -->
268
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]269<div class="doc_text">
270
271<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]272component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]273sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]274href="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]275there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]276
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]277</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]278
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]279<!-- ======================================================================= -->
280<div class="doc_subsection">
281 <a name="experimental">Experimental features included with this release</a>
282</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]283
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]284<div class="doc_text">
285
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]286<p>The following components of this LLVM release are either untested, known to
287be broken or unreliable, or are in early development. These components should
288not be relied on, and bugs should not be filed against them, but they may be
289useful to some people. In particular, if you would like to work on one of these
290components, please contact us on the llvmdev list.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]291
292<ul>
Misha Brukman467ea6b2004-08-05 21:04:03 +0000[diff] [blame]293<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
294benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
295details.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]296<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner09f3ac92004-09-14 16:43:13 +0000[diff] [blame]297 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]298<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
299 it should) and not thoroughly tested.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]300<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
301</ul>
302
303</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]304
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]305<!-- ======================================================================= -->
306<div class="doc_subsection">
307 <a name="core">Known problems with the LLVM Core</a>
308</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]309
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]310<div class="doc_text">
311
312<ul>
313
314<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
315work.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]316
317<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]318such, execution of a threaded program could cause these data structures to be
319corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]320
Chris Lattnerc0171082004-08-08 03:33:07 +0000[diff] [blame]321<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]322table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]323
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]324<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
325objects/archives in the order specified on the command line.</a></li>
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]326
327<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]328values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]329targets whose setjmp/longjmp libraries do not save and restore the entire
330register file.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]331</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]332</div>
333
334<!-- ======================================================================= -->
335<div class="doc_subsection">
336 <a name="c-fe">Known problems with the C front-end</a>
337</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]338
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]339<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]340<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]341
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]342<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]343<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]344<li>C99 Variable sized arrays do not release stack memory when they go out of
345 scope. Thus, the following program may run out of stack space:
346<pre>
347 for (i = 0; i != 1000000; ++i) {
348 int X[n];
349 foo(X);
350 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]351</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]352
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]353<li>Initialization of global union variables can only be done <a
354href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
355member</a>.</li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]356
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]357<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
358external function is re-declared as static</a></li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]359
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]360</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]361</div>
362
363<!-- _______________________________________________________________________ -->
364<div class="doc_subsubsection">
365 Notes
366</div>
367
368<div class="doc_text">
369
370<ul>
371
372<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]373
374<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]375support for floating point data types of any size other than 32 and 64
376bits.</li>
377
378<li>The following Unix system functionality has not been tested and may not
379work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]380 <ol>
381 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
382 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
383 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
384 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
385 - These functions have not been tested.
386 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]387
388<li>Although many GCC extensions are supported, some are not. In particular,
389 the following extensions are known to <b>not be</b> supported:
390 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]391 <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]392 <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>
393 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
394 <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]395 <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]396 <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>
397 <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]398 <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>
399 <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>
400 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
401 <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]402 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]403
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]404 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]405 attribute means that the LLVM compiler ignores the presence of the attribute,
406 but the code should still work. An unsupported attribute is one which is
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]407 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]408 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]409
410 <ol>
411 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
412 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]413 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]414
415 <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]416
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]417 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]418 return.<br>
419
420 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
421 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
422 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
423
424 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
425 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
426 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
427
428 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
429 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
430 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]431
432 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
433 Specifying attributes of variables.<br>
434 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
435 <tt>deprecated</tt>, <tt>transparent_union</tt>,
436 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]437
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]438 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
439 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
440 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]441 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]442
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]443 <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]444 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]445 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]446
447 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
448 all target specific attributes.</li>
449
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]450 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
451 Other built-in functions.<br>
452 We support all builtins which have a C language equivalent (e.g.,
453 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
454 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerb7c4bac2004-06-18 06:26:29 +0000[diff] [blame]455 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
456 (currently ignored). We also support builtins for ISO C99 floating
457 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]458 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]459
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]460 <p>The following extensions <b>are</b> known to be supported:</p>
461
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]462 <ol>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]463 <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]464 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
465 <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]466 <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]467 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
468 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
469 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
470 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
471 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
472 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
473 <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>
474 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
475 <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]476 <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]477 <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]478 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
479or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]480 <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]481 <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]482 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
483 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
484 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
485 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
486 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
487 <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>
488 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
489 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
490 <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>
491 <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>
492 <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]493 <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]494 <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>
495 <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]496 </ol></li>
497
498</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]499
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]500<p>If you run into GCC extensions which have not been included in any of these
501lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]502
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]503</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]504
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]505<!-- ======================================================================= -->
506<div class="doc_subsection">
507 <a name="c++-fe">Known problems with the C++ front-end</a>
508</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]509
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]510<div class="doc_text">
511
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]512<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]513has not been tested as thoroughly as the C front-end. It has been tested and
514works for a number of non-trivial programs, but there may be lurking bugs.
515Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]516
517</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]518
519<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]520<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]521
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]522<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]523
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]524<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]525<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]526 front-end</a>.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]527
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]528<li><b>IA-64 specific</b>: The C++ front-end does not use <a
529href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]530In particular, it just stores function pointers instead of function
531descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner2fd93492004-08-02 20:29:51 +0000[diff] [blame]532LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]533
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]534</ul>
535
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]536</div>
537
538<!-- _______________________________________________________________________ -->
539<div class="doc_subsubsection">
540 Notes
541</div>
542
543<div class="doc_text">
544
545<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]546
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]547<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
548parser is significantly more standards compliant (and picky) than prior GCC
549versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]550href="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]551
552<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]553 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]554 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]555 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]556 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]557
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]558<li>The LLVM C++ front-end follows the <a
559 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
560 This document, which is not Itanium specific, specifies a standard for name
561 mangling, class layout, v-table layout, RTTI formats, and other C++
562 representation issues. Because we use this API, code generated by the LLVM
563 compilers should be binary compatible with machine code generated by other
564 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
565 <i>However</i>, the exception handling mechanism used by LLVM is very
566 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]567 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]568
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]569</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]570
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]571</div>
572
573<!-- ======================================================================= -->
574<div class="doc_subsection">
575 <a name="x86-be">Known problems with the X86 back-end</a>
576</div>
577
578<div class="doc_text">
579
580<ul>
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]581 <li>none yet</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]582</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]583
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]584</div>
585
586<!-- ======================================================================= -->
587<div class="doc_subsection">
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]588 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]589</div>
590
591<div class="doc_text">
592
593<ul>
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]594<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
595several programs in the LLVM test suite</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]596</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]597
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]598</div>
599
600<!-- ======================================================================= -->
601<div class="doc_subsection">
Chris Lattnerdf925ce2004-11-07 01:55:32 +0000[diff] [blame]602 <a name="ppc-be">Known problems with the PowerPC back-end</a>
603</div>
604
605<div class="doc_text">
606
607<ul>
608<li>none yet</li>
609</ul>
610
611</div>
612
613<!-- ======================================================================= -->
614<div class="doc_subsection">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]615 <a name="c-be">Known problems with the C back-end</a>
616</div>
617
618<div class="doc_text">
619
620<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]621
622<li>The C back-end produces code that violates the ANSI C Type-Based Alias
623Analysis rules. As such, special options may be necessary to compile the code
624(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]625problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]626
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]627<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]628cannot include special floating point numbers like Not-A-Number or
629Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]630
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]631<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]632supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]633frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]634
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]635</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]636
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]637</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]638
639<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]640<div class="doc_section">
641 <a name="additionalinfo">Additional Information</a>
642</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]643<!-- *********************************************************************** -->
644
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]645<div class="doc_text">
646
647<p>A wide variety of additional information is available on the LLVM web page,
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]648including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]649implemented in LLVM. The web page also contains versions of the API
650documentation which is up-to-date with the CVS version of the source code. You
651can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]652the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]653
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]654<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]655us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
656lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]657
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]658</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]659
660<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]661
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]662<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]663<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]664 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]665 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
666 <a href="http://validator.w3.org/check/referer"><img
667 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
668
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]669 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]670 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]671</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]672
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]673</body>
674</html>