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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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4<head>
5 <link rel="stylesheet" href="llvm.css" type="text/css">
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]6 <title>LLVM 1.3 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]7</head>
8<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]9
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]10<div class="doc_title">LLVM 1.3 Release Notes</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]11
12<ol>
Misha Brukman500bc302003-11-22 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 Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]15 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]16 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]17 <li><a href="#knownproblems">Known Problems</a>
18 <ul>
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]19 <li><a href="#experimental">Experimental features included in this
20 release</a>
Chris Lattner79c3fe12003-10-02 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>
25 <li><a href="#sparc-be">Known problems with the Sparc Back-end</a>
26 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]27 </ul></li>
28 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]29</ol>
30
Chris Lattner7911ce22004-05-23 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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]33</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]34
35<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]36<div class="doc_section">
37 <a name="intro">Introduction</a>
38</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]39<!-- *********************************************************************** -->
40
Misha Brukman500bc302003-11-22 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 Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]44infrastructure, release 1.3. Here we describe the status of LLVM, including any
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]45known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]46version of this document can be found on the <a
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]47href="http://llvm.cs.uiuc.edu/releases/1.3/">LLVM 1.3 web site</a>. If you are
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]48not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]49this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]50
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]51<p>For more information about LLVM, including information about potentially more
Chris Lattner47ad72c2003-10-07 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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]55list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]56
Chris Lattner9e848092003-12-12 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 Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]60href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
61
62</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]63
64<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]65<div class="doc_section">
66 <a name="whatsnew">What's New?</a>
67</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]68<!-- *********************************************************************** -->
69
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]70<div class="doc_text">
71
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]72<p>This is the fourth public release of the LLVM compiler infrastructure. This
Chris Lattnerd4594dc2004-05-04 17:04:09 +0000[diff] [blame]73release primarily improves the <a href="#codequality">performance of the
74code</a> produced by all aspects of the LLVM compiler and adds some <a
75href="#newfeatures">new features</a>, though it does <a href="#bugfix">fix a few
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]76bugs</a> as well.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]77
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]78<p> At this time, LLVM is known to correctly compile and run all C &amp; C++
79SPEC CPU2000 benchmarks, the Olden benchmarks, and the Ptrdist benchmarks. It
80has also been used to compile <b>many</b> other programs. LLVM now also works
81with a broad variety of C++ programs, though it has still received less testing
82than the C front-end.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]83
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]84</div>
85
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]86<!--=========================================================================-->
87<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]88<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]89</div>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]90
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]91<div class="doc_text">
92
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]93<ol>
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]94<li>The LLVM <a href="LangRef.html#i_select"><tt>select</tt></a> instruction is
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]95now fully implemented and supported by all transformations, native code
96generators, and the interpreter.</li>
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]97<li>Bugpoint can now narrow down code-generation bugs to a loop nest, where
98before it could only narrow them down to a function being miscompiled.</li>
Brian Gaeke43be3112004-05-04 21:22:57 +0000[diff] [blame]99<li><a href="http://llvm.cs.uiuc.edu/PR40">Bugpoint can now debug arbitrary
100modes of llc</a> and lli, by passing them command line flags (e.g.,
101<tt>-regalloc=linearscan</tt>, <tt>-enable-correct-eh-support</tt>, etc.) </li>
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]102<li>The Control Flow Graph in the native code generators is no longer
103constrained to be the same as the CFG for the LLVM input code.</li>
104<li>The LLVM induction variable analysis routines have been rewritten.</li>
105<li>LLVM now has new loop unrolling and loop unswitching passes.</li>
106<li>The induction variable substitution pass performs linear function test
107replacement and exit value replacement optimizations.</li>
Chris Lattnerb9656692004-05-24 04:53:32 +0000[diff] [blame]108<li>The <a href="BytecodeFormat.html">LLVM Bytecode file format</a> is now
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]109 documented.</li>
Chris Lattner39491a72004-05-24 04:45:52 +0000[diff] [blame]110<li>LLVM now has first-class support for <a href="GarbageCollection.html">Accurate
111Garbage Collection</a>, enabling the use of aggressive copying and generational
112collectors.</li>
113<li>LLVM now includes an implementation of Andersen's interprocedural alias
114analysis algorithm.</li>
Chris Lattner14cd5392004-05-24 05:34:32 +0000[diff] [blame]115<li>Bugpoint can <a href="http://llvm.cs.uiuc.edu/PR327">extract individual
116basic blocks</a> to track down reduce miscompilation testcases.</li>
Brian Gaeke5beb8ba2004-06-01 20:02:56 +0000[diff] [blame]117<li>LLVM and the C front-end now work under Win32 using the
118<a href="http://www.cygwin.com">Cygwin</a> runtime libraries.
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]119This includes the JIT compiler.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]120</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]121
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]122</div>
123
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]124
125<!--=========================================================================-->
126<div class="doc_subsubsection">
127In this release, the following missing features were implemented:
128</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]129
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]130<div class="doc_text">
131
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]132<ol>
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]133<li><a href="http://llvm.cs.uiuc.edu/PR82">LLVM cannot handle structures with
134more than 256 elements</a></li>
Misha Brukmancb003362004-04-19 03:01:01 +0000[diff] [blame]135<li><a href="http://llvm.cs.uiuc.edu/PR38">[bugpoint] External functions used in
136non-instruction entities, such as global constant initializer</a></li>
Reid Spencer44ff57a2004-05-09 23:32:39 +0000[diff] [blame]137<li><a href="http://llvm.cs.uiuc.edu/PR178">Stacker does not handle targets
138with 64-bit pointers.</a></li>
Misha Brukmancb003362004-04-19 03:01:01 +0000[diff] [blame]139<li><a href="http://llvm.cs.uiuc.edu/PR290">Bugpoint doesn't support
140uses of external fns by immediate constant exprs</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]141</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]142
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]143</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]144
145<!--=========================================================================-->
146<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]147<a name="qualityofimp">In this release, the following Quality of Implementation
148issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]149</div>
150
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]151<div class="doc_text">
152
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]153<ol>
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]154<li><a href="http://llvm.cs.uiuc.edu/PR305">LLVM tools will happily spew
155bytecode onto your terminal</a></li>
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]156<li><a href="http://llvm.cs.uiuc.edu/PR329">[llvmgcc] type names are not emitted
157for structure typedefs</a></li>
Chris Lattnerb9656692004-05-24 04:53:32 +0000[diff] [blame]158<li>All documentation is now conformant to the HTML 4.01 (Strict) level.</li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]159</ol>
160
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]161</div>
162
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]163<!--=========================================================================-->
164<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]165In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]166</div>
167
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]168<div class="doc_text">
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]169<ol>
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]170<li><a href="http://llvm.cs.uiuc.edu/PR301">Minor configure bugs with
171-disable/enable-povray and -disable-spec</a></li>
172<li><a href="http://llvm.cs.uiuc.edu/PR289">shell scripts output by gccld don't
173work if you change PATH</a></li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]174</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]175</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]176
177<!--=========================================================================-->
178<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]179<a name="codequality">This release includes the following Code Quality
180improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]181</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]182
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]183<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]184<ol>
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]185<li>Fixed: <a href="http://llvm.cs.uiuc.edu/PR309">[vmcore] Code quality problem
186due to long operand of getelementptr</a></li>
Chris Lattner64913402004-04-13 14:43:35 +0000[diff] [blame]187
188<li>The X86 backend now generates substantially better code for 64-bit integer
189and floating point operations.</li>
190
191<li>The -inline pass no longer inlines mutually recursive functions until it
192hits the inlining threshold.</li>
193
194<li>The -inline pass no longer misses obvious inlining opportunities just
195because the callee eventually calls into an external function.</li>
196
197<li>The -simplifycfg pass can now "if convert" simple statements into the new
198<tt>select</tt> instruction.</li>
199
200<li>The -loopsimplify pass can now break <a
201href="http://llvm.cs.uiuc.edu/PR35">natural loops with multiple backedges</a>
202into multiple nested loops. This enables a variety of subsequent
203optimizations.</li>
204
205<li>The -adce pass can now eliminate calls to functions that do not not write to
206memory.</li>
207
208<li>The link-time optimizer now runs the -prune-eh pass (to remove unused
Chris Lattnerd4594dc2004-05-04 17:04:09 +0000[diff] [blame]209exception handlers).</li>
Chris Lattner64913402004-04-13 14:43:35 +0000[diff] [blame]210
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]211<li>The -simplifycfg pass can now eliminate simple correlated branches (such as
212"<tt>if (A &lt; B &amp;&amp; A &lt; B)</tt>", and can turn short-circuiting
213operators into the strict versions when useful (such as "<tt>if (A &lt; B || A
214&gt; C)</tt>" into "<tt>if (A &lt; B | A &gt; C)</tt>"</li>
215
Chris Lattnerd4594dc2004-05-04 17:04:09 +0000[diff] [blame]216<li>LLVM now has infrastructure for (simple and sparse conditional) constant
217propagation of function calls. It currently supports a few math library
218functions like sqrt/sin/cos/etc.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]219</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]220</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]221
222<!--=========================================================================-->
223<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]224<a name="bugfix">In this release, the following bugs in the previous release
225were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]226</div>
227
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]228<div class="doc_text">
229
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]230<p>Bugs in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]231
232<ol>
John Criswell4d8d49f2004-05-06 22:23:24 +0000[diff] [blame]233<li><a href="http://llvm.cs.uiuc.edu/PR330">[vmcore] Linker causes erroneous
234asssertion</a></li>
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]235<li><a href="http://llvm.cs.uiuc.edu/PR306">[loopsimplify] Loop simplify
236incorrectly updates dominator information</a></li>
237<li><a href="http://llvm.cs.uiuc.edu/PR310">[tailduplicate] DemoteRegToStack
238breaks SSA form</a></li>
239<li><a href="http://llvm.cs.uiuc.edu/PR313">[X86] JIT miscompiles unsigned short
240to floating point cast</a></li>
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]241<li><a href="http://llvm.cs.uiuc.edu/PR332">[adce] Crash handling unreachable
242code that unwinds</a></li>
243<li><a href="http://llvm.cs.uiuc.edu/PR333">[sparc] LLC can't emit 2 functions
244of the same name, both having constant pools</a></li>
245<li><a href="http://llvm.cs.uiuc.edu/PR337">[livevar] Live variables missed
246physical register use of aliased definition</a></li>
Chris Lattnere5ad10a2004-05-21 16:48:20 +0000[diff] [blame]247<li><a href="http://llvm.cs.uiuc.edu/PR340">Verifier misses malformed switch instruction</a></li>
Chris Lattneraec5f262004-06-01 21:52:45 +0000[diff] [blame]248<li><a href="http://llvm.cs.uiuc.edu/PR315">[jit] abort, don't warn, when missing external functions encountered</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]249</ol>
250
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]251<p>Bugs in the C/C++ front-end:</p>
252
253<ol>
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]254<li><a href="http://llvm.cs.uiuc.edu/PR326">[llvmgcc] Crash on use of undeclared
255enum type</a></li>
256<li><a href="http://llvm.cs.uiuc.edu/PR298">[llvmgcc] Variable length array
257indexing miscompiled</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]258</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]259</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]260
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]261<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]262<div class="doc_section">
263 <a name="portability">Portability and Supported Platforms</a>
264</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]265<!-- *********************************************************************** -->
266
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]267<div class="doc_text">
268
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]269<p>LLVM is known to work in the following platforms:</p>
270
271<ul>
272<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
273 other unix-like systems).</li>
274<li>Sun UltraSPARC workstations running Solaris 8.</li>
275<li>PowerPC-based Mac OS X boxes, running 10.3 and above (C backend and
276 interpreter only, no native codegen is available yet).</li>
277<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
278</ul>
279
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]280
281<p>The core LLVM infrastructure uses
282<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
283to the machine and operating system on which it is built. However, minor
284porting may be required to get LLVM to work on new platforms. We welcome your
285portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]286
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]287<p>Note that the LLVM build system does not currently support directories with
288spaces on them when running on Win32/cygwin. We strongly recommend running
289LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]290<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
291cygwin packages. By default, many important tools are not installed that
292are needed by the LLVM build process or test suite (e.g., /bin/time).</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]293
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]294</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]295
Brian Gaeke21a710a2004-04-20 18:18:46 +0000[diff] [blame]296<!--=========================================================================-->
297<div class="doc_subsection">
298In this release, the following portability problems were fixed:
299</div>
300
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]301<div class="doc_text">
302
Brian Gaeke21a710a2004-04-20 18:18:46 +0000[diff] [blame]303<ol>
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]304<li><a href="http://llvm.cs.uiuc.edu/PR304">warnings compiling Stacker compiler
305on Mac OS X</a></li>
306<li><a href="http://llvm.cs.uiuc.edu/PR308">Archive file reader doesn't
307understand abbreviated names in headers</a></li>
Brian Gaeke21a710a2004-04-20 18:18:46 +0000[diff] [blame]308</ol>
309
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]310</div>
311
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]312<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]313<div class="doc_section">
314 <a name="knownproblems">Known Problems</a>
315</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]316<!-- *********************************************************************** -->
317
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]318<div class="doc_text">
319
320<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]321component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]322sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]323href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]324there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]325
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]326</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]327
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]328<!-- ======================================================================= -->
329<div class="doc_subsection">
330 <a name="experimental">Experimental features included with this release</a>
331</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]332
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]333<div class="doc_text">
334
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]335<p>The following components of this LLVM release are either untested, known to
336be broken or unreliable, or are in early development. These components should
337not be relied on, and bugs should not be filed against them, but they may be
338useful to some people. In particular, if you would like to work on one of these
339components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]340
341<ul>
342<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
343 -ipmodref, -sortstructs, -swapstructs, -cee</tt></li>
344
345<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
346 it should) and not thoroughly tested.</li>
347<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
348<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
349</ul>
350
351</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]352
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]353<!-- ======================================================================= -->
354<div class="doc_subsection">
355 <a name="core">Known problems with the LLVM Core</a>
356</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]357
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]358<div class="doc_text">
359
360<ul>
361
362<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
363work.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]364
365<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]366such, execution of a threaded program could cause these data structures to be
367corrupted.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]368
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]369<li>It is not possible to <tt>dlopen</tt> an LLVM bytecode file in the JIT.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]370
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]371<li>Linking in static archive files (.a files) is very slow (there is no symbol
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]372table in the archive).</li>
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]373
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]374<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
375objects/archives in the order specified on the command line.</a></li>
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]376
377<li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not mark
John Criswelld46c6962004-03-12 21:29:42 +0000[diff] [blame]378values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattner2e6fcaf2004-02-15 23:09:07 +0000[diff] [blame]379targets whose setjmp/longjmp libraries do not save and restore the entire
380register file.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]381</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]382</div>
383
384<!-- ======================================================================= -->
385<div class="doc_subsection">
386 <a name="c-fe">Known problems with the C front-end</a>
387</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]388
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]389<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]390<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]391
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]392<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]393<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]394<li>C99 Variable sized arrays do not release stack memory when they go out of
395 scope. Thus, the following program may run out of stack space:
396<pre>
397 for (i = 0; i != 1000000; ++i) {
398 int X[n];
399 foo(X);
400 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]401</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]402
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]403<li>Initialization of global union variables can only be done <a
404href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
405member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]406
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]407<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
408external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]409
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]410</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]411</div>
412
413<!-- _______________________________________________________________________ -->
414<div class="doc_subsubsection">
415 Notes
416</div>
417
418<div class="doc_text">
419
420<ul>
421
422<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]423
424<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]425support for floating point data types of any size other than 32 and 64
426bits.</li>
427
428<li>The following Unix system functionality has not been tested and may not
429work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]430 <ol>
431 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
432 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
433 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
434 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
435 - These functions have not been tested.
436 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]437
438<li>Although many GCC extensions are supported, some are not. In particular,
439 the following extensions are known to <b>not be</b> supported:
440 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]441 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]442 <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>
443 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
444 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Extended%20Asm">Extended Asm</a>: Assembler instructions with C expressions as operands.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]445 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]446 <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>
447 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Explicit-Reg-Vars.html#Explicit%20Reg%20Vars">Explicit Reg Vars</a>: Defining variables residing in specified registers.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]448 <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>
449 <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>
450 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
451 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li>
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]452 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]453
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]454 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]455 attribute means that the LLVM compiler ignores the presence of the attribute,
456 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]457 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]458 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]459
460 <ol>
461 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
462 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]463 Supported, but allocated stack space is not freed until the function returns (noted above).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]464
465 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>:
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]466
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]467 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]468 return.<br>
469
470 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
471 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
472 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
473
474 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
475 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
476 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
477
478 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
479 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
480 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]481
482 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
483 Specifying attributes of variables.<br>
484 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
485 <tt>deprecated</tt>, <tt>transparent_union</tt>,
486 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]487
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]488 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
489 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
490 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]491 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]492
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]493 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.<br>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]494 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]495 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]496
497 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
498 all target specific attributes.</li>
499
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]500 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
501 Other built-in functions.<br>
502 We support all builtins which have a C language equivalent (e.g.,
503 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
504 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]505 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]506
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]507 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]508
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]509 <p>The following extensions <b>are</b> known to be supported:</p>
510
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]511 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]512 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html#Labels%20as%20Values">Labels as Values</a>: Getting pointers to labels and computed gotos.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]513 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
514 <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>
515 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
516 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
517 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
518 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
519 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
520 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
521 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
522 <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>
523 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
524 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Subscripting.html#Subscripting">Subscripting</a>: Any array can be subscripted, even if not an lvalue.</li>
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]525 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pointer-Arith.html#Pointer%20Arith">Pointer Arith</a>: Arithmetic on <code>void</code>-pointers and function pointers.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]526 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]527 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
528or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]529 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]530 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Cast-to-Union.html#Cast%20to%20Union">Cast to Union</a>: Casting to union type from any member of the union.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]531 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
532 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
533 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
534 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
535 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
536 <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>
537 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
538 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
539 <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>
540 <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>
541 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Names.html#Function%20Names">Function Names</a>: Printable strings which are the name of the current function.</li>
Chris Lattner25795bc2004-02-14 04:08:29 +0000[diff] [blame]542 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Return-Address.html#Return%20Address">Return Address</a>: Getting the return or frame address of a function.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]543 <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>
544 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute%20Syntax">Attribute Syntax</a>: Formal syntax for attributes.</li>
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]545 </ol></li>
546
547</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]548
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]549<p>If you run into GCC extensions which have not been included in any of these
550lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]551
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]552</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]553
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]554<!-- ======================================================================= -->
555<div class="doc_subsection">
556 <a name="c++-fe">Known problems with the C++ front-end</a>
557</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]558
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]559<div class="doc_text">
560
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]561<p>For this release, the C++ front-end is considered to be fully functional but
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]562has not been tested as thoroughly as the C front-end. It has been tested and
563works for a number of non-trivial programs, but there may be lurking bugs.
564Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]565
566</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]567
568<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]569<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]570
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]571<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]572
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]573<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]574<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]575 front-end</a>.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]576</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]577</div>
578
579<!-- _______________________________________________________________________ -->
580<div class="doc_subsubsection">
581 Notes
582</div>
583
584<div class="doc_text">
585
586<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]587
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]588<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
589parser is significantly more standards compliant (and picky) than prior GCC
590versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]591href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]592
593<li>Destructors for local objects are not always run when a <tt>longjmp</tt> is
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]594 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]595 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]596 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]597 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]598
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]599<li>The LLVM C++ front-end follows the <a
600 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
601 This document, which is not Itanium specific, specifies a standard for name
602 mangling, class layout, v-table layout, RTTI formats, and other C++
603 representation issues. Because we use this API, code generated by the LLVM
604 compilers should be binary compatible with machine code generated by other
605 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
606 <i>However</i>, the exception handling mechanism used by LLVM is very
607 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]608 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]609
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]610</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]611
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]612</div>
613
614<!-- ======================================================================= -->
615<div class="doc_subsection">
616 <a name="x86-be">Known problems with the X86 back-end</a>
617</div>
618
619<div class="doc_text">
620
621<ul>
Chris Lattnerde4afdc2004-02-08 22:23:33 +0000[diff] [blame]622<li>None so far.
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]623</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]624
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]625</div>
626
627<!-- ======================================================================= -->
628<div class="doc_subsection">
629 <a name="sparc-be">Known problems with the Sparc back-end</a>
630</div>
631
632<div class="doc_text">
633
634<ul>
Chris Lattner6a39aa52004-03-19 19:22:28 +0000[diff] [blame]635<li>There are several programs in the LLVM testsuite that the Sparc code generator is known to miscompile.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]636</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]637
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]638</div>
639
640<!-- ======================================================================= -->
641<div class="doc_subsection">
642 <a name="c-be">Known problems with the C back-end</a>
643</div>
644
645<div class="doc_text">
646
647<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]648
649<li>The C back-end produces code that violates the ANSI C Type-Based Alias
650Analysis rules. As such, special options may be necessary to compile the code
651(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]652problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]653
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]654<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]655cannot include special floating point numbers like Not-A-Number or
656Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]657
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]658<li><a href="http://llvm.cs.uiuc.edu/PR56">Zero arg vararg functions are not
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]659supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]660frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]661
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]662</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]663
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]664</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]665
666<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]667<div class="doc_section">
668 <a name="additionalinfo">Additional Information</a>
669</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]670<!-- *********************************************************************** -->
671
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]672<div class="doc_text">
673
674<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]675including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]676implemented in LLVM. The web page also contains versions of the API
677documentation which is up-to-date with the CVS version of the source code. You
678can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]679the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]680
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]681<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]682us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
683lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]684
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]685</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]686
687<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]688
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]689<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]690<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]691 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]692 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
693 <a href="http://validator.w3.org/check/referer"><img
694 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
695
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]696 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]697 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]698</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]699
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]700</body>
701</html>