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