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gerrit-public.fairphone.software / toolchain / llvm-project / 850f85f81fb2168ffc7895651a8698247588d1dd / . / llvm / docs / ReleaseNotes.html
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Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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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 Lattnereda4f472004-05-24 04:45:52 +0000[diff] [blame]108<li>LLVM now has first-class support for <a href="GarbageCollection.html">Accurate
109Garbage Collection</a>, enabling the use of aggressive copying and generational
110collectors.</li>
111<li>LLVM now includes an implementation of Andersen's interprocedural alias
112analysis algorithm.</li>
Chris Lattner57e7a4c2004-05-24 05:34:32 +0000[diff] [blame]113<li>Bugpoint can <a href="http://llvm.cs.uiuc.edu/PR327">extract individual
114basic blocks</a> to track down reduce miscompilation testcases.</li>
Brian Gaeke84c8bd02004-06-01 20:02:56 +0000[diff] [blame]115<li>LLVM and the C front-end now work under Win32 using the
116<a href="http://www.cygwin.com">Cygwin</a> runtime libraries.
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]117This includes the JIT compiler.</li>
Chris Lattnera7fac952004-06-04 00:40:11 +0000[diff] [blame]118<li>The LLVM code generator is now being <a
119 href="CodeGenerator.html">documented</a>.</li>
Reid Spencer850f85f2004-06-08 07:30:31 +0000[diff] [blame^]120<li>There is a new tool, llvm-abcd, the Analysis of ByteCode Dumper (abcd).
121This tool can compute basic statistics and bytecode density statistics on a
122module or function basis and also dump out bytecode in a textual format that
123is lower level than assembly (values are not resolved from slot numbers).
124It should only be of interest to (a) those who are working to improve the
125bytecode format and (b) those who really want to understand or document the
126details of the bytecode format.</li>
127<li>The <a href="BytecodeFormat.html">LLVM Bytecode file format</a> is now
128 being documented.</li>
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]129</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]130
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]131</div>
132
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]133
134<!--=========================================================================-->
135<div class="doc_subsubsection">
136In this release, the following missing features were implemented:
137</div>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]138
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]139<div class="doc_text">
140
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]141<ol>
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]142<li><a href="http://llvm.cs.uiuc.edu/PR82">LLVM cannot handle structures with
143more than 256 elements</a></li>
Misha Brukmane7050232004-04-19 03:01:01 +0000[diff] [blame]144<li><a href="http://llvm.cs.uiuc.edu/PR38">[bugpoint] External functions used in
145non-instruction entities, such as global constant initializer</a></li>
Reid Spencer45e25d82004-05-09 23:32:39 +0000[diff] [blame]146<li><a href="http://llvm.cs.uiuc.edu/PR178">Stacker does not handle targets
147with 64-bit pointers.</a></li>
Misha Brukmane7050232004-04-19 03:01:01 +0000[diff] [blame]148<li><a href="http://llvm.cs.uiuc.edu/PR290">Bugpoint doesn't support
149uses of external fns by immediate constant exprs</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]150</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]151
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]152</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]153
154<!--=========================================================================-->
155<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]156<a name="qualityofimp">In this release, the following Quality of Implementation
157issues were fixed:</a>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]158</div>
159
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]160<div class="doc_text">
161
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]162<ol>
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]163<li><a href="http://llvm.cs.uiuc.edu/PR305">LLVM tools will happily spew
164bytecode onto your terminal</a></li>
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]165<li><a href="http://llvm.cs.uiuc.edu/PR329">[llvmgcc] type names are not emitted
166for structure typedefs</a></li>
Chris Lattnerf10ccbf2004-05-24 04:53:32 +0000[diff] [blame]167<li>All documentation is now conformant to the HTML 4.01 (Strict) level.</li>
Chris Lattnerbd948cf2004-06-08 07:19:29 +0000[diff] [blame]168<li>The spurious "WARNING: Found global types that are not compatible" warning
169produced when linking C++ programs has been fixed.</li>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]170</ol>
171
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]172</div>
173
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]174<!--=========================================================================-->
175<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]176In this release, the following build problems were fixed:
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]177</div>
178
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]179<div class="doc_text">
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]180<ol>
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]181<li><a href="http://llvm.cs.uiuc.edu/PR301">Minor configure bugs with
182-disable/enable-povray and -disable-spec</a></li>
183<li><a href="http://llvm.cs.uiuc.edu/PR289">shell scripts output by gccld don't
184work if you change PATH</a></li>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]185</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]186</div>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]187
188<!--=========================================================================-->
189<div class="doc_subsubsection">
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]190<a name="codequality">This release includes the following Code Quality
191improvements:</a>
Chris Lattner23257062004-05-23 20:42:08 +0000[diff] [blame]192</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]193
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]194<div class="doc_text">
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]195<ol>
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]196<li>Fixed: <a href="http://llvm.cs.uiuc.edu/PR309">[vmcore] Code quality problem
197due to long operand of getelementptr</a></li>
Chris Lattner54dcea82004-04-13 14:43:35 +0000[diff] [blame]198
199<li>The X86 backend now generates substantially better code for 64-bit integer
200and floating point operations.</li>
201
202<li>The -inline pass no longer inlines mutually recursive functions until it
203hits the inlining threshold.</li>
204
205<li>The -inline pass no longer misses obvious inlining opportunities just
206because the callee eventually calls into an external function.</li>
207
208<li>The -simplifycfg pass can now "if convert" simple statements into the new
209<tt>select</tt> instruction.</li>
210
211<li>The -loopsimplify pass can now break <a
212href="http://llvm.cs.uiuc.edu/PR35">natural loops with multiple backedges</a>
213into multiple nested loops. This enables a variety of subsequent
214optimizations.</li>
215
216<li>The -adce pass can now eliminate calls to functions that do not not write to
217memory.</li>
218
219<li>The link-time optimizer now runs the -prune-eh pass (to remove unused
Chris Lattnerea309ff2004-05-04 17:04:09 +0000[diff] [blame]220exception handlers).</li>
Chris Lattner54dcea82004-04-13 14:43:35 +0000[diff] [blame]221
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]222<li>The -simplifycfg pass can now eliminate simple correlated branches (such as
223"<tt>if (A &lt; B &amp;&amp; A &lt; B)</tt>", and can turn short-circuiting
224operators into the strict versions when useful (such as "<tt>if (A &lt; B || A
225&gt; C)</tt>" into "<tt>if (A &lt; B | A &gt; C)</tt>"</li>
226
Chris Lattnerea309ff2004-05-04 17:04:09 +0000[diff] [blame]227<li>LLVM now has infrastructure for (simple and sparse conditional) constant
228propagation of function calls. It currently supports a few math library
229functions like sqrt/sin/cos/etc.</li>
Chris Lattner249b3552004-06-03 22:35:13 +0000[diff] [blame]230
231<li>The C backend now emits <a href="http://llvm.cs.uiuc.edu/PR334">Syntactic
232loops</a> in the code to help C compilers whose optimizers do not recognize
233loops formed from gotos (like GCC).</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]234</ol>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]235</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]236
237<!--=========================================================================-->
238<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]239<a name="bugfix">In this release, the following bugs in the previous release
240were fixed:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]241</div>
242
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]243<div class="doc_text">
244
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]245<p>Bugs in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]246
247<ol>
John Criswell6956afa2004-05-06 22:23:24 +0000[diff] [blame]248<li><a href="http://llvm.cs.uiuc.edu/PR330">[vmcore] Linker causes erroneous
249asssertion</a></li>
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]250<li><a href="http://llvm.cs.uiuc.edu/PR306">[loopsimplify] Loop simplify
251incorrectly updates dominator information</a></li>
252<li><a href="http://llvm.cs.uiuc.edu/PR310">[tailduplicate] DemoteRegToStack
253breaks SSA form</a></li>
254<li><a href="http://llvm.cs.uiuc.edu/PR313">[X86] JIT miscompiles unsigned short
255to floating point cast</a></li>
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]256<li><a href="http://llvm.cs.uiuc.edu/PR332">[adce] Crash handling unreachable
257code that unwinds</a></li>
258<li><a href="http://llvm.cs.uiuc.edu/PR333">[sparc] LLC can't emit 2 functions
259of the same name, both having constant pools</a></li>
260<li><a href="http://llvm.cs.uiuc.edu/PR337">[livevar] Live variables missed
261physical register use of aliased definition</a></li>
Chris Lattner8f7cf272004-05-21 16:48:20 +0000[diff] [blame]262<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]263<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]264</ol>
265
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]266<p>Bugs in the C/C++ front-end:</p>
267
268<ol>
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]269<li><a href="http://llvm.cs.uiuc.edu/PR326">[llvmgcc] Crash on use of undeclared
270enum type</a></li>
271<li><a href="http://llvm.cs.uiuc.edu/PR298">[llvmgcc] Variable length array
272indexing miscompiled</a></li>
Chris Lattner25b3a032004-06-08 07:15:52 +0000[diff] [blame]273<li><a href="http://llvm.cs.uiuc.edu/PR355">[llvmgcc] Errors handling function prototypes that take opaque structs by-value</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]274</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]275</div>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]276
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]277<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]278<div class="doc_section">
279 <a name="portability">Portability and Supported Platforms</a>
280</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]281<!-- *********************************************************************** -->
282
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]283<div class="doc_text">
284
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]285<p>LLVM is known to work in the following platforms:</p>
286
287<ul>
288<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
289 other unix-like systems).</li>
290<li>Sun UltraSPARC workstations running Solaris 8.</li>
291<li>PowerPC-based Mac OS X boxes, running 10.3 and above (C backend and
292 interpreter only, no native codegen is available yet).</li>
293<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
294</ul>
295
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]296
297<p>The core LLVM infrastructure uses
298<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
299to the machine and operating system on which it is built. However, minor
300porting may be required to get LLVM to work on new platforms. We welcome your
301portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]302
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]303<p>Note that the LLVM build system does not currently support directories with
304spaces on them when running on Win32/cygwin. We strongly recommend running
305LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattnerce1a3842004-06-01 19:41:30 +0000[diff] [blame]306<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
307cygwin packages. By default, many important tools are not installed that
308are needed by the LLVM build process or test suite (e.g., /bin/time).</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]309
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]310</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]311
Brian Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]312<!--=========================================================================-->
313<div class="doc_subsection">
314In this release, the following portability problems were fixed:
315</div>
316
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]317<div class="doc_text">
318
Brian Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]319<ol>
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]320<li><a href="http://llvm.cs.uiuc.edu/PR304">warnings compiling Stacker compiler
321on Mac OS X</a></li>
322<li><a href="http://llvm.cs.uiuc.edu/PR308">Archive file reader doesn't
323understand abbreviated names in headers</a></li>
Brian Gaeke86a6c752004-04-20 18:18:46 +0000[diff] [blame]324</ol>
325
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]326</div>
327
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]328<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]329<div class="doc_section">
330 <a name="knownproblems">Known Problems</a>
331</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]332<!-- *********************************************************************** -->
333
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]334<div class="doc_text">
335
336<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]337component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]338sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]339href="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]340there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]341
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]342</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]343
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]344<!-- ======================================================================= -->
345<div class="doc_subsection">
346 <a name="experimental">Experimental features included with this release</a>
347</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]348
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]349<div class="doc_text">
350
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]351<p>The following components of this LLVM release are either untested, known to
352be broken or unreliable, or are in early development. These components should
353not be relied on, and bugs should not be filed against them, but they may be
354useful to some people. In particular, if you would like to work on one of these
355components, please contact us on the llvmdev list.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]356
357<ul>
358<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
359 -ipmodref, -sortstructs, -swapstructs, -cee</tt></li>
360
361<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
362 it should) and not thoroughly tested.</li>
363<li>The <tt>llvm-ar</tt> tool is incomplete and probably buggy.</li>
364<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
365</ul>
366
367</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]368
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]369<!-- ======================================================================= -->
370<div class="doc_subsection">
371 <a name="core">Known problems with the LLVM Core</a>
372</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]373
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]374<div class="doc_text">
375
376<ul>
377
378<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
379work.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]380
381<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]382such, execution of a threaded program could cause these data structures to be
383corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]384
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]385<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]386
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]387<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]388table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]389
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]390<li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
391objects/archives in the order specified on the command line.</a></li>
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]392
393<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]394values live across a setjmp as volatile</a>. This missing feature only affects
Chris Lattneraebc66a2004-02-15 23:09:07 +0000[diff] [blame]395targets whose setjmp/longjmp libraries do not save and restore the entire
396register file.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]397</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]398</div>
399
400<!-- ======================================================================= -->
401<div class="doc_subsection">
402 <a name="c-fe">Known problems with the C front-end</a>
403</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]404
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]405<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]406<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]407
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]408<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]409<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]410<li>C99 Variable sized arrays do not release stack memory when they go out of
411 scope. Thus, the following program may run out of stack space:
412<pre>
413 for (i = 0; i != 1000000; ++i) {
414 int X[n];
415 foo(X);
416 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]417</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]418
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]419<li>Initialization of global union variables can only be done <a
420href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
421member</a>.</li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]422
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]423<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
424external function is re-declared as static</a></li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]425
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]426</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]427</div>
428
429<!-- _______________________________________________________________________ -->
430<div class="doc_subsubsection">
431 Notes
432</div>
433
434<div class="doc_text">
435
436<ul>
437
438<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]439
440<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]441support for floating point data types of any size other than 32 and 64
442bits.</li>
443
444<li>The following Unix system functionality has not been tested and may not
445work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]446 <ol>
447 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
448 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
449 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
450 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
451 - These functions have not been tested.
452 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]453
454<li>Although many GCC extensions are supported, some are not. In particular,
455 the following extensions are known to <b>not be</b> supported:
456 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]457 <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]458 <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>
459 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
460 <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]461 <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]462 <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>
463 <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]464 <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>
465 <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>
466 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
467 <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]468 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]469
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]470 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]471 attribute means that the LLVM compiler ignores the presence of the attribute,
472 but the code should still work. An unsupported attribute is one which is
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]473 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]474 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]475
476 <ol>
477 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
478 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]479 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]480
481 <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]482
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]483 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]484 return.<br>
485
486 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
487 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
488 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
489
490 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
491 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
492 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
493
494 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
495 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
496 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]497
498 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
499 Specifying attributes of variables.<br>
500 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
501 <tt>deprecated</tt>, <tt>transparent_union</tt>,
502 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]503
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]504 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
505 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
506 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]507 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]508
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]509 <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]510 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]511 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]512
513 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
514 all target specific attributes.</li>
515
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]516 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
517 Other built-in functions.<br>
518 We support all builtins which have a C language equivalent (e.g.,
519 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
520 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]521 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]522
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]523 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]524
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]525 <p>The following extensions <b>are</b> known to be supported:</p>
526
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]527 <ol>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]528 <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]529 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
530 <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>
531 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
532 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
533 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
534 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
535 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
536 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
537 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
538 <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>
539 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
540 <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]541 <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]542 <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]543 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
544or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]545 <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]546 <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]547 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
548 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
549 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
550 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
551 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
552 <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>
553 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
554 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
555 <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>
556 <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>
557 <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]558 <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]559 <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>
560 <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]561 </ol></li>
562
563</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]564
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]565<p>If you run into GCC extensions which have not been included in any of these
566lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]567
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]568</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]569
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]570<!-- ======================================================================= -->
571<div class="doc_subsection">
572 <a name="c++-fe">Known problems with the C++ front-end</a>
573</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]574
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]575<div class="doc_text">
576
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]577<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]578has not been tested as thoroughly as the C front-end. It has been tested and
579works for a number of non-trivial programs, but there may be lurking bugs.
580Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]581
582</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]583
584<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]585<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]586
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]587<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]588
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]589<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]590<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]591 front-end</a>.</li>
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]592</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]593</div>
594
595<!-- _______________________________________________________________________ -->
596<div class="doc_subsubsection">
597 Notes
598</div>
599
600<div class="doc_text">
601
602<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]603
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]604<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
605parser is significantly more standards compliant (and picky) than prior GCC
606versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]607href="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]608
609<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]610 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]611 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]612 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]613 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]614
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]615<li>The LLVM C++ front-end follows the <a
616 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
617 This document, which is not Itanium specific, specifies a standard for name
618 mangling, class layout, v-table layout, RTTI formats, and other C++
619 representation issues. Because we use this API, code generated by the LLVM
620 compilers should be binary compatible with machine code generated by other
621 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
622 <i>However</i>, the exception handling mechanism used by LLVM is very
623 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]624 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]625
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]626</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]627
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]628</div>
629
630<!-- ======================================================================= -->
631<div class="doc_subsection">
632 <a name="x86-be">Known problems with the X86 back-end</a>
633</div>
634
635<div class="doc_text">
636
637<ul>
Chris Lattnerc5b7b242004-02-08 22:23:33 +0000[diff] [blame]638<li>None so far.
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]639</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]640
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]641</div>
642
643<!-- ======================================================================= -->
644<div class="doc_subsection">
645 <a name="sparc-be">Known problems with the Sparc back-end</a>
646</div>
647
648<div class="doc_text">
649
650<ul>
Chris Lattner9e0b81c2004-03-19 19:22:28 +0000[diff] [blame]651<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]652</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]653
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]654</div>
655
656<!-- ======================================================================= -->
657<div class="doc_subsection">
658 <a name="c-be">Known problems with the C back-end</a>
659</div>
660
661<div class="doc_text">
662
663<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]664
665<li>The C back-end produces code that violates the ANSI C Type-Based Alias
666Analysis rules. As such, special options may be necessary to compile the code
667(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]668problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]669
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]670<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]671cannot include special floating point numbers like Not-A-Number or
672Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]673
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]674<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]675supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]676frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]677
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]678</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]679
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]680</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]681
682<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]683<div class="doc_section">
684 <a name="additionalinfo">Additional Information</a>
685</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]686<!-- *********************************************************************** -->
687
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]688<div class="doc_text">
689
690<p>A wide variety of additional information is available on the LLVM web page,
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]691including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]692implemented in LLVM. The web page also contains versions of the API
693documentation which is up-to-date with the CVS version of the source code. You
694can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]695the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]696
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]697<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]698us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
699lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]700
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]701</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]702
703<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]704
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]705<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]706<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]707 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]708 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
709 <a href="http://validator.w3.org/check/referer"><img
710 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
711
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]712 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]713 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]714</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]715
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]716</body>
717</html>