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Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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4<head>
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Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]6 <title>LLVM 1.3 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 Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]10<div class="doc_title">LLVM 1.3 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>
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 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 Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]44infrastructure, release 1.3. 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 Lattner1a7e43c2004-04-01 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 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
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]72<p>This is the fourth public release of the LLVM compiler infrastructure. This
Chris Lattnerea309ff2004-05-04 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 Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]76bugs</a> as well.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]77
Misha Brukmanfa50a222004-05-12 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 Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]83
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]84</div>
85
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]86<!--=========================================================================-->
87<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]88<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]89</div>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]90
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]91<div class="doc_text">
92
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]93<ol>
Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]94<li>The LLVM <a href="LangRef.html#i_select"><tt>select</tt></a> instruction is
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]95now fully implemented and supported by all transformations, native code
96generators, and the interpreter.</li>
Misha Brukman017f2f32004-04-19 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 Gaekee307f8a72004-05-04 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 Lattner2ad48782004-05-02 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 Lattnerf10ccbf2004-05-24 04:53:32 +0000[diff] [blame]108<li>The <a href="BytecodeFormat.html">LLVM Bytecode file format</a> is now
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]109 documented.</li>
Chris Lattnereda4f472004-05-24 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 Lattner57e7a4c2004-05-24 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 Gaeke84c8bd02004-06-01 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 Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]119This includes the JIT compiler.</li>
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]120</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]121
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]122</div>
123
Chris Lattnerba7bd472003-12-06 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 Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]129
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]130<div class="doc_text">
131
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]132<ol>
Misha Brukman017f2f32004-04-19 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 Brukmane7050232004-04-19 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 Spencer45e25d82004-05-09 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 Brukmane7050232004-04-19 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]141</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]142
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]143</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]144
145<!--=========================================================================-->
146<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]147<a name="qualityofimp">In this release, the following Quality of Implementation
148issues were fixed:</a>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]149</div>
150
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]151<div class="doc_text">
152
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]153<ol>
Misha Brukman017f2f32004-04-19 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 Brukmanfa50a222004-05-12 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 Lattnerf10ccbf2004-05-24 04:53:32 +0000[diff] [blame]158<li>All documentation is now conformant to the HTML 4.01 (Strict) level.</li>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]159</ol>
160
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]161</div>
162
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]163<!--=========================================================================-->
164<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]165In this release, the following build problems were fixed:
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]166</div>
167
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]168<div class="doc_text">
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]169<ol>
Misha Brukmanfa50a222004-05-12 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 Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]174</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]175</div>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]176
177<!--=========================================================================-->
178<div class="doc_subsubsection">
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]179<a name="codequality">This release includes the following Code Quality
180improvements:</a>
Chris Lattner23257062004-05-23 20:42:08 +0000[diff] [blame]181</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]182
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]183<div class="doc_text">
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]184<ol>
Chris Lattner2ad48782004-05-02 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 Lattner54dcea82004-04-13 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 Lattnerea309ff2004-05-04 17:04:09 +0000[diff] [blame]209exception handlers).</li>
Chris Lattner54dcea82004-04-13 14:43:35 +0000[diff] [blame]210
Chris Lattner2ad48782004-05-02 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 Lattnerea309ff2004-05-04 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]219</ol>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]220</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]221
222<!--=========================================================================-->
223<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]224<a name="bugfix">In this release, the following bugs in the previous release
225were fixed:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]226</div>
227
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]228<div class="doc_text">
229
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]230<p>Bugs in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]231
232<ol>
John Criswell6956afa2004-05-06 22:23:24 +0000[diff] [blame]233<li><a href="http://llvm.cs.uiuc.edu/PR330">[vmcore] Linker causes erroneous
234asssertion</a></li>
Misha Brukman017f2f32004-04-19 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 Brukmanfa50a222004-05-12 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 Lattner8f7cf272004-05-21 16:48:20 +0000[diff] [blame]247<li><a href="http://llvm.cs.uiuc.edu/PR340">Verifier misses malformed switch instruction</a></li>
Chris Lattner3edb94b2004-06-01 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 Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]249</ol>
250
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]251<p>Bugs in the C/C++ front-end:</p>
252
253<ol>
Misha Brukmanfa50a222004-05-12 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 Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]258</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]259</div>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]260
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]261<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]262<div class="doc_section">
263 <a name="portability">Portability and Supported Platforms</a>
264</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]265<!-- *********************************************************************** -->
266
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]267<div class="doc_text">
268
Chris Lattner2c7b0872004-06-01 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 Gaekee3e557e2004-05-09 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]286
Chris Lattner2c7b0872004-06-01 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 Lattnerce1a3842004-06-01 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 Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]293
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]294</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]295
Brian Gaeke86a6c752004-04-20 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 Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]301<div class="doc_text">
302
Brian Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]303<ol>
Misha Brukmanfa50a222004-05-12 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 Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]308</ol>
309
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]310</div>
311
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]312<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]313<div class="doc_section">
314 <a name="knownproblems">Known Problems</a>
315</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]316<!-- *********************************************************************** -->
317
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]321component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]322sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]323href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]324there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]325
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]326</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]327
Chris Lattnerb911de42004-03-14 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]332
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]333<div class="doc_text">
334
Misha Brukmanfa50a222004-05-12 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 Lattnerb911de42004-03-14 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]352
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]357
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]364
365<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]366such, execution of a threaded program could cause these data structures to be
367corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]368
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]370
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]371<li>Linking in static archive files (.a files) is very slow (there is no symbol
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]372table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]373
Misha Brukman017f2f32004-04-19 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 Lattneraebc66a2004-02-15 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 Criswell5d6345a2004-03-12 21:29:42 +0000[diff] [blame]378values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]379targets whose setjmp/longjmp libraries do not save and restore the entire
380register file.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]381</ul>
Misha Brukman80731b92003-11-22 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 Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]388
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]389<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]390<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]391
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]392<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]393<ul>
Chris Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]401</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]402
Misha Brukmanfa50a222004-05-12 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 Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]406
Misha Brukman017f2f32004-04-19 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 Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]409
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]410</ul>
Misha Brukman80731b92003-11-22 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 Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]423
424<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 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 Brukman7cb4e382003-11-22 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 Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 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 Brukman80731b92003-11-22 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 Criswell86a3a482003-12-18 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 Brukman80731b92003-11-22 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 Brukman80731b92003-11-22 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 Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]452 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]453
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]454 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 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 Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]457 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]458 the program.</p>
Chris Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]463 Supported, but allocated stack space is not freed until the function returns (noted above).</li>
Chris Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]466
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]467 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]487
Chris Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]491 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]492
Misha Brukman8395d732003-12-12 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]494 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]495 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]505 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]506
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]507 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]508
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]509 <p>The following extensions <b>are</b> known to be supported:</p>
510
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]511 <ol>
Chris Lattnerd3dc8502004-03-16 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 Brukman80731b92003-11-22 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 Brukman8395d732003-12-12 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 Brukman80731b92003-11-22 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 Criswell86a3a482003-12-18 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 Brukman80731b92003-11-22 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 Brukman8395d732003-12-12 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 Brukman80731b92003-11-22 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 Lattner3646dad2004-02-14 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 Brukman80731b92003-11-22 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 Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]545 </ol></li>
546
547</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]548
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]551
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]552</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]553
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]558
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]559<div class="doc_text">
560
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]561<p>For this release, the C++ front-end is considered to be fully functional but
Chris Lattnere76e9ab2003-12-12 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]565
566</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]567
568<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]569<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]570
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]571<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]572
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]573<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]574<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]575 front-end</a>.</li>
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]576</ul>
Misha Brukman80731b92003-11-22 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 Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]587
Chris Lattner3d482502003-10-02 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 Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]591href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]592
593<li>Destructors for local objects are not always run when a <tt>longjmp</tt> is
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]594 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]595 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]596 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]597 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]598
Chris Lattner62495762003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]608 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]609
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]610</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]611
Misha Brukman80731b92003-11-22 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 Lattnerc5b7b242004-02-08 22:23:33 +0000[diff] [blame]622<li>None so far.
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]623</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]624
Misha Brukman80731b92003-11-22 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 Lattner9e0b81c2004-03-19 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]636</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]637
Misha Brukman80731b92003-11-22 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 Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]652problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]653
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]654<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]655cannot include special floating point numbers like Not-A-Number or
656Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]657
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]658<li><a href="http://llvm.cs.uiuc.edu/PR56">Zero arg vararg functions are not
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]659supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]660frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]661
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]662</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]663
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]664</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]665
666<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]667<div class="doc_section">
668 <a name="additionalinfo">Additional Information</a>
669</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]670<!-- *********************************************************************** -->
671
Misha Brukman80731b92003-11-22 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 Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]675including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]679the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]680
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]681<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]682us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
683lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]684
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]685</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]686
687<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]688
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]689<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]690<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]691 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman68aab3b2003-11-22 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 Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]696 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]697 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]698</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]699
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]700</body>
701</html>