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gerrit-public.fairphone.software / toolchain / llvm-project / 615ffb84faeea4fe30c033d95f490ffaaf6f822b / . / llvm / docs / ReleaseNotes.html
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Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]6 <title>LLVM 1.4 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]7</head>
8<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]9
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]10<div class="doc_title">LLVM 1.4 Release Notes</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]11
12<ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]13 <li><a href="#intro">Introduction</a></li>
14 <li><a href="#whatsnew">What's New?</a></li>
Chris Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]15 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]16 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]17 <li><a href="#knownproblems">Known Problems</a>
18 <ul>
Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]19 <li><a href="#experimental">Experimental features included in this
20 release</a>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]21 <li><a href="#core">Known problems with the LLVM Core</a>
22 <li><a href="#c-fe">Known problems with the C Front-end</a>
23 <li><a href="#c++-fe">Known problems with the C++ Front-end</a>
24 <li><a href="#x86-be">Known problems with the X86 Back-end</a>
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]25 <li><a href="#sparcv9-be">Known problems with the SparcV9 Back-end</a>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]26 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]27 </ul></li>
28 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]29</ol>
30
Chris Lattner020e1fc2004-05-23 21:07:27 +0000[diff] [blame]31<div class="doc_author">
32 <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]33</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]34
35<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]36<div class="doc_section">
37 <a name="intro">Introduction</a>
38</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]39<!-- *********************************************************************** -->
40
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]41<div class="doc_text">
42
43<p>This document contains the release notes for the LLVM compiler
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]44infrastructure, release 1.4. Here we describe the status of LLVM, including any
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]45known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]46version of this document can be found on the <a
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]47href="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]48not reading this on the LLVM web pages, you should probably go there because
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]49this document may be updated after the release.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]50
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]51<p>For more information about LLVM, including information about potentially more
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]52current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main
53web site</a>. If you have questions or comments, the <a
54href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]55list</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]56
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]57<p>Note that if you are reading this file from CVS, this document applies
58to the <i>next</i> release, not the current one. To see the release notes for
59the current or previous releases, see the <a
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]60href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
61
62</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]63
64<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]65<div class="doc_section">
66 <a name="whatsnew">What's New?</a>
67</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]68<!-- *********************************************************************** -->
69
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]70<div class="doc_text">
71
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]72<p>This is the fifth public release of the LLVM compiler infrastructure.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]73
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]74<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]75SPEC CPU95 &amp; 2000 benchmarks, the Olden benchmarks, and the Ptrdist
76benchmarks, and <b>many</b> other programs. LLVM now also works
77with a broad variety of C++ programs.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]78
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]79</div>
80
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]81<!--=========================================================================-->
82<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]83<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]84</div>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]85
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]86<div class="doc_text">
87
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]88<ol>
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]89<li></li>
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]90</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]91
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]92</div>
93
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]94
95<!--=========================================================================-->
96<div class="doc_subsubsection">
97In this release, the following missing features were implemented:
98</div>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]99
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]100<div class="doc_text">
101
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]102<ol>
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]103<li><a href="http://llvm.org/PR419">JIT interface should support arbitrary
104 calls</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]105</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]106
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]107</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]108
109<!--=========================================================================-->
110<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]111<a name="qualityofimp">In this release, the following Quality of Implementation
112issues were fixed:</a>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]113</div>
114
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]115<div class="doc_text">
116
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]117<ol>
Chris Lattner615ffb82004-08-20 00:36:23 +0000[diff] [blame^]118<li><a href="http://llvm.org/PR426">[llvmg++] Tons of warnings are spewed when
119 linking to libstdc++</a></li>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]120</ol>
121
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]122</div>
123
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]124<!--=========================================================================-->
125<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]126In this release, the following build problems were fixed:
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]127</div>
128
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]129<div class="doc_text">
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]130<ol>
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]131<li></li>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]132</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]133</div>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]134
135<!--=========================================================================-->
136<div class="doc_subsubsection">
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]137<a name="codequality">This release includes the following Code Quality
138improvements:</a>
Chris Lattner23257062004-05-23 20:42:08 +0000[diff] [blame]139</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]140
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]141<div class="doc_text">
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]142<ol>
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]143<li></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]144</ol>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]145</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]146
147<!--=========================================================================-->
148<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]149<a name="bugfix">In this release, the following bugs in the previous release
150were fixed:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]151</div>
152
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]153<div class="doc_text">
154
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]155<p>Bugs fixed in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]156
157<ol>
Reid Spencerf03b47c2004-08-16 16:48:19 +0000[diff] [blame]158<li><a href="http://llvm.org/PR422">[asmwriter] Asmwriter is really slow for
159 functions with lots of values</a></li>
Chris Lattnera10ed3b2004-08-16 05:46:57 +0000[diff] [blame]160<li><a href="http://llvm.org/PR423">[anders-aa] Andersen's AA is completely
161 broken in LLVM 1.3</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]162</ol>
163
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]164<p>Bugs in the C/C++ front-end:</p>
165
166<ol>
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]167<li></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]168</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]169</div>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]170
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]171<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]172<div class="doc_section">
173 <a name="portability">Portability and Supported Platforms</a>
174</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]175<!-- *********************************************************************** -->
176
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]177<div class="doc_text">
178
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]179<p>LLVM is known to work in the following platforms:</p>
180
181<ul>
182<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
183 other unix-like systems).</li>
184<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]185<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnerd21e3d02004-08-05 21:53:13 +0000[diff] [blame]186<li>PowerPC-based Mac OS X boxes, running 10.2 and above. Note that no JIT
187support is available yet, and LLC support is beta. The C backend can be used
188to produce stable code for this platform.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]189</ul>
190
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]191<p>The core LLVM infrastructure uses
192<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
193to the machine and operating system on which it is built. However, minor
194porting may be required to get LLVM to work on new platforms. We welcome your
195portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]196
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]197<p>Note that the LLVM build system does not currently support directories with
198spaces on them when running on Win32/cygwin. We strongly recommend running
199LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattnerce1a3842004-06-01 19:41:30 +0000[diff] [blame]200<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
201cygwin packages. By default, many important tools are not installed that
Chris Lattnera752fce2004-08-16 20:20:46 +0000[diff] [blame]202are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
203please make sure that there are no directories with spaces in them in your
204PATH environment variable.</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]205
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]206</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]207
208<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]209<div class="doc_section">
210 <a name="knownproblems">Known Problems</a>
211</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]212<!-- *********************************************************************** -->
213
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]214<div class="doc_text">
215
216<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]217component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]218sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]219href="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]220there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]221
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]222</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]223
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]224<!-- ======================================================================= -->
225<div class="doc_subsection">
226 <a name="experimental">Experimental features included with this release</a>
227</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]228
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]229<div class="doc_text">
230
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]231<p>The following components of this LLVM release are either untested, known to
232be broken or unreliable, or are in early development. These components should
233not be relied on, and bugs should not be filed against them, but they may be
234useful to some people. In particular, if you would like to work on one of these
235components, please contact us on the llvmdev list.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]236
237<ul>
Misha Brukman467ea6b2004-08-05 21:04:03 +0000[diff] [blame]238<li>The PowerPC backend is incomplete and is known to miscompile several SPEC
239benchmarks. The file <tt>llvm/lib/Target/PowerPC/README.txt</tt> has
240details.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]241<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner99583502004-06-28 00:44:45 +0000[diff] [blame]242 -ipmodref, -cee</tt></li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]243<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
244 it should) and not thoroughly tested.</li>
245<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
246<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
247</ul>
248
249</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]250
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]251<!-- ======================================================================= -->
252<div class="doc_subsection">
253 <a name="core">Known problems with the LLVM Core</a>
254</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]255
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]256<div class="doc_text">
257
258<ul>
259
260<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
261work.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]262
263<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]264such, execution of a threaded program could cause these data structures to be
265corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]266
Chris Lattnerc0171082004-08-08 03:33:07 +0000[diff] [blame]267<li>Linking in static archive files (.a files) is slow (there is no symbol
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]268table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]269
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]270<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
271objects/archives in the order specified on the command line.</a></li>
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]272
273<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]274values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]275targets whose setjmp/longjmp libraries do not save and restore the entire
276register file.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]277</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]278</div>
279
280<!-- ======================================================================= -->
281<div class="doc_subsection">
282 <a name="c-fe">Known problems with the C front-end</a>
283</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]284
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]285<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]286<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]287
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]288<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]289<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]290<li>C99 Variable sized arrays do not release stack memory when they go out of
291 scope. Thus, the following program may run out of stack space:
292<pre>
293 for (i = 0; i != 1000000; ++i) {
294 int X[n];
295 foo(X);
296 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]297</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]298
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]299<li>Initialization of global union variables can only be done <a
300href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
301member</a>.</li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]302
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]303<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
304external function is re-declared as static</a></li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]305
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]306</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]307</div>
308
309<!-- _______________________________________________________________________ -->
310<div class="doc_subsubsection">
311 Notes
312</div>
313
314<div class="doc_text">
315
316<ul>
317
318<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]319
320<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]321support for floating point data types of any size other than 32 and 64
322bits.</li>
323
324<li>The following Unix system functionality has not been tested and may not
325work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]326 <ol>
327 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
328 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
329 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
330 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
331 - These functions have not been tested.
332 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]333
334<li>Although many GCC extensions are supported, some are not. In particular,
335 the following extensions are known to <b>not be</b> supported:
336 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]337 <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]338 <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>
339 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
340 <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]341 <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]342 <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>
343 <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]344 <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>
345 <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>
346 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
347 <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]348 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]349
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]350 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]351 attribute means that the LLVM compiler ignores the presence of the attribute,
352 but the code should still work. An unsupported attribute is one which is
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]353 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]354 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]355
356 <ol>
357 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
358 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]359 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]360
361 <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]362
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]363 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]364 return.<br>
365
366 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
367 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
368 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
369
370 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
371 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
372 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
373
374 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
375 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
376 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]377
378 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
379 Specifying attributes of variables.<br>
380 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
381 <tt>deprecated</tt>, <tt>transparent_union</tt>,
382 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]383
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]384 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
385 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
386 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]387 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]388
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]389 <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]390 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]391 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]392
393 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
394 all target specific attributes.</li>
395
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]396 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
397 Other built-in functions.<br>
398 We support all builtins which have a C language equivalent (e.g.,
399 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
400 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerb7c4bac2004-06-18 06:26:29 +0000[diff] [blame]401 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
402 (currently ignored). We also support builtins for ISO C99 floating
403 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]404 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]405
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]406 <p>The following extensions <b>are</b> known to be supported:</p>
407
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]408 <ol>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]409 <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]410 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
411 <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]412 <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]413 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
414 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
415 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
416 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
417 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
418 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
419 <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>
420 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
421 <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]422 <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]423 <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]424 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
425or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]426 <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]427 <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]428 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
429 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
430 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
431 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
432 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
433 <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>
434 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
435 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
436 <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>
437 <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>
438 <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]439 <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]440 <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>
441 <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]442 </ol></li>
443
444</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]445
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]446<p>If you run into GCC extensions which have not been included in any of these
447lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]448
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]449</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]450
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]451<!-- ======================================================================= -->
452<div class="doc_subsection">
453 <a name="c++-fe">Known problems with the C++ front-end</a>
454</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]455
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]456<div class="doc_text">
457
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]458<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]459has not been tested as thoroughly as the C front-end. It has been tested and
460works for a number of non-trivial programs, but there may be lurking bugs.
461Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]462
463</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]464
465<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]466<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]467
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]468<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]469
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]470<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]471<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]472 front-end</a>.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]473
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]474<li><b>IA-64 specific</b>: The C++ front-end does not use <a
475href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]476In particular, it just stores function pointers instead of function
477descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner2fd93492004-08-02 20:29:51 +0000[diff] [blame]478LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]479
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]480</ul>
481
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]482</div>
483
484<!-- _______________________________________________________________________ -->
485<div class="doc_subsubsection">
486 Notes
487</div>
488
489<div class="doc_text">
490
491<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]492
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]493<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
494parser is significantly more standards compliant (and picky) than prior GCC
495versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]496href="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]497
498<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]499 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]500 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]501 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]502 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]503
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]504<li>The LLVM C++ front-end follows the <a
505 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
506 This document, which is not Itanium specific, specifies a standard for name
507 mangling, class layout, v-table layout, RTTI formats, and other C++
508 representation issues. Because we use this API, code generated by the LLVM
509 compilers should be binary compatible with machine code generated by other
510 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
511 <i>However</i>, the exception handling mechanism used by LLVM is very
512 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]513 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]514
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]515</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]516
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]517</div>
518
519<!-- ======================================================================= -->
520<div class="doc_subsection">
521 <a name="x86-be">Known problems with the X86 back-end</a>
522</div>
523
524<div class="doc_text">
525
526<ul>
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]527 <li>none yet</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]528</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]529
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]530</div>
531
532<!-- ======================================================================= -->
533<div class="doc_subsection">
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]534 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]535</div>
536
537<div class="doc_text">
538
539<ul>
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]540<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
541several programs in the LLVM test suite</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]542</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]543
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]544</div>
545
546<!-- ======================================================================= -->
547<div class="doc_subsection">
548 <a name="c-be">Known problems with the C back-end</a>
549</div>
550
551<div class="doc_text">
552
553<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]554
555<li>The C back-end produces code that violates the ANSI C Type-Based Alias
556Analysis rules. As such, special options may be necessary to compile the code
557(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]558problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]559
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]560<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]561cannot include special floating point numbers like Not-A-Number or
562Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]563
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]564<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]565supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]566frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]567
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]568</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]569
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]570</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]571
572<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]573<div class="doc_section">
574 <a name="additionalinfo">Additional Information</a>
575</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]576<!-- *********************************************************************** -->
577
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]578<div class="doc_text">
579
580<p>A wide variety of additional information is available on the LLVM web page,
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]581including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]582implemented in LLVM. The web page also contains versions of the API
583documentation which is up-to-date with the CVS version of the source code. You
584can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]585the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]586
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]587<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]588us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
589lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]590
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]591</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]592
593<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]594
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]595<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]596<address>
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Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]602 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]603 Last modified: $Date$
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