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6 <title>LLVM 1.1 Release Notes</title>
7</head>
8<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]9
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]10<div class="doc_title">
11 LLVM 1.1 Release Notes
12</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]13
14<ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]15 <li><a href="#intro">Introduction</a></li>
16 <li><a href="#whatsnew">What's New?</a></li>
17 <li><a href="#portability">Portability and Supported Platforms</a></li>
18 <li><a href="#install-instructions">Installation Instructions</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]19 <li><a href="#knownproblems">Known Problems</a>
20 <ul>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]21<!-- <li><a href="#portabilityprobs">Portability Problems</a> -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]22 <li><a href="#core">Known problems with the LLVM Core</a>
23 <li><a href="#c-fe">Known problems with the C Front-end</a>
24 <li><a href="#c++-fe">Known problems with the C++ Front-end</a>
25 <li><a href="#x86-be">Known problems with the X86 Back-end</a>
26 <li><a href="#sparc-be">Known problems with the Sparc Back-end</a>
27 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]28 </ul></li>
29 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]30</ol>
31
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]32<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]33 <p><b>Written by <a href="mailto:sabre@nondot.org">Chris Lattner</a></b><p>
34</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]35
36<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]37<div class="doc_section">
38 <a name="intro">Introduction</a>
39</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]40<!-- *********************************************************************** -->
41
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]42<div class="doc_text">
43
44<p>This document contains the release notes for the LLVM compiler
45infrastructure, release 1.1. Here we describe the status of LLVM, including any
46known problems, and bug fixes from the previous release. The most up-to-date
47version of this document can be found on the <a
Chris Lattner7c4bd1d2003-10-27 01:31:14 +0000[diff] [blame]48href="http://llvm.cs.uiuc.edu/releases/1.1/">LLVM 1.1 web site</a>. If you are
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]49not reading this on the LLVM web pages, you should probably go there, because
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]50this document may be updated after the release.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]51
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]52<p>For more information about LLVM, including information about potentially more
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]53current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main
54web site</a>. If you have questions or comments, the <a
55href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]56list</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]57
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]58<p>Note that if you are reading this file from CVS, this document applies
59to the <i>next</i> release, not the current one. To see the release notes for
60the current or previous releases, see the <a
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]61href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
62
63</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]64
65<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]66<div class="doc_section">
67 <a name="whatsnew">What's New?</a>
68</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]69<!-- *********************************************************************** -->
70
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]71<div class="doc_text">
72
73<p>This is the second public release of the LLVM compiler infrastructure. This
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]74release is primarily a bugfix release, dramatically improving the C/C++
75front-end, and improving support for C++ in the LLVM core. This release also
Chris Lattnerd98fecb2003-12-06 20:24:46 +0000[diff] [blame]76includes a few new features, such as a simple profiler, support for Mac OS/X,
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]77better interoperability with external source bases, and improves a few
78optimizations.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]79
Chris Lattnere4151eb2003-12-11 23:31:21 +0000[diff] [blame]80<p>At this time, LLVM is known to correctly compile the C &amp; C++ SPEC CPU2000
81benchmarks (X86 only), the Olden benchmarks, and the Ptrdist benchmarks along
82with <b>many</b> other programs. LLVM now also works with a broad variety of
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]83C++ programs, though it has still received much less testing than the C
84front-end.
85</p>
86
87<p>
88Note that the Sparc and X86 backends do not currently support exception throwing
89or long jumping (including 253.perlbmk in SPEC). For these programs, you must
90use the C backend. Support for unwinding will be added in a future release.
91</p>
92
93
94<!--=========================================================================-->
95<div class="doc_subsubsection">
96This release implements the following new features:
97</div>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]98
99<ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]100<li><a
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]101href="http://mail.cs.uiuc.edu/pipermail/llvmdev/2003-November/000528.html">A new
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]102LLVM profiler, similar to gprof</a> is available</li>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]103
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]104<li>LLVM and the C/C++ front-end now compile on Mac OS/X! Mac OS/X users can
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]105now explore the LLVM optimizer with the C backend and interpreter. Note that
106LLVM requires GCC 3.3 on Mac OS/X.</li>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]107
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]108<li>LLVM has been <a
Chris Lattner74a22992003-11-11 23:46:35 +0000[diff] [blame]109href="http://mail.cs.uiuc.edu/pipermail/llvmdev/2003-November/000554.html">moved
110into an 'llvm' C++ namespace</a>, for easier integration with third-party
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]111code. Note that due to lack of namespace support in GDB 5.x, you will probably
112want to upgrade to GDB 6 or better to debug LLVM code.</li>
John Criswellf1387a52003-11-26 20:09:49 +0000[diff] [blame]113
114<li>
115The build system now copies Makefiles dynamically from the source tree to the
116object tree as subdirectories are built. This means that:
117 <ol>
118 <li>
119 New directories can be added to the source tree, and the build will
120 automatically pick them up (i.e. no need to re-run <tt>configure</tt>).
121 </li>
122
123 <li>
124 You will need to build LLVM from the top of the object tree once to ensure
125 that all of the Makefiles are copied into the object tree subdirectories.
126 </li>
127 </ol>
128</li>
129
Chris Lattnere4151eb2003-12-11 23:31:21 +0000[diff] [blame]130<li>The <tt>configure</tt> script will now configure all projects placed in the
131<tt>llvm/projects</tt> directory.</li>
132
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]133<li>The <tt>-licm</tt> pass can now sink instructions out the bottom of loops
134in addition to being able to hoist them out the top.</li>
135
136
137<li>The <tt>-basicaa</tt> pass (the default alias analysis) has been upgraded
138to be <a href="http://llvm.cs.uiuc.edu/PR86">significantly more
139precise</a>.</li>
Chris Lattnere4151eb2003-12-11 23:31:21 +0000[diff] [blame]140
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]141</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]142
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]143
144<!--=========================================================================-->
145<div class="doc_subsubsection">
146In this release, the following missing features were implemented:
147</div>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]148
149<ol>
150<li><a href="http://llvm.cs.uiuc.edu/PR88">The interpreter does not support
151invoke or unwind</a></li>
Misha Brukman133b35e2003-11-14 03:30:43 +0000[diff] [blame]152
153<li><a href="http://llvm.cs.uiuc.edu/PR99">Interpreter does not support the
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]154<tt>vaarg</tt> instruction</a></li>
Misha Brukman133b35e2003-11-14 03:30:43 +0000[diff] [blame]155
Brian Gaekec5961312003-11-16 23:49:26 +0000[diff] [blame]156<li><a href="http://llvm.cs.uiuc.edu/PR117">llvm-nm cannot read archive
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]157files</a></li>
Brian Gaekec5961312003-11-16 23:49:26 +0000[diff] [blame]158
Brian Gaeke4c563b82003-12-11 04:40:58 +0000[diff] [blame]159<li><a href="http://llvm.cs.uiuc.edu/PR146">Interpreter does not handle
160setne constant expression</a></li>
161
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]162</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]163
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]164
165<!--=========================================================================-->
166<div class="doc_subsubsection">
167In this release, the following Quality of Implementation issues were
168fixed:
169</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]170
171<ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]172
173<li><a href="http://llvm.cs.uiuc.edu/PR29">C++ front-end is not generating
174linkonce linkage type when it can</a></li>
175
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]176<li><a href="http://llvm.cs.uiuc.edu/PR84">C front-end generates non-type-safe code for expressions it could generate type-safe code</a></li>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]177
Chris Lattnerb2e4d6d2003-11-16 20:25:24 +0000[diff] [blame]178<li><a href="http://llvm.cs.uiuc.edu/PR96">Bad path to the C/C++ frontend causes
179build problems</a></li>
180
181<li><a href="http://llvm.cs.uiuc.edu/PR114">LLVM header files should be -Wold-style-cast clean</a></li>
182
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]183<li>The LLVM bytecode reader has been <a
184href="http://llvm.cs.uiuc.edu/PR127">sped up a lot</a> (up to 4x in some
185cases).</li>
186
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]187<li>In C++, methods and functions in anonymous namespaces <a href="http://llvm.cs.uiuc.edu/PR85">now get internal linkage</a>.</li>
Chris Lattner3a9b2322003-11-22 01:14:58 +0000[diff] [blame]188
Chris Lattner0548bc22003-11-26 08:20:34 +0000[diff] [blame]189<li>Constant initializers now generate loops instead of potentially <a href="http://llvm.cs.uiuc.edu/PR75">huge amounts of straight-line code</a>.</li>
190
Chris Lattner8139b782003-11-27 09:51:54 +0000[diff] [blame]191<li>Code for running C++ destructors is now properly shared when possible. Before, the C++ front-end
192<a href="http://llvm.cs.uiuc.edu/PR11">generated N^2 amounts of duplicated cleanup code</a> in some cases.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]193</ol>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]194
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]195
196<!--=========================================================================-->
197<div class="doc_subsubsection">
198In this release, the following bugs in the previous release were fixed:
199</div>
200
201<p>Bugs in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]202
203<ol>
Chris Lattner25fd5c12003-10-27 05:41:39 +0000[diff] [blame]204<li><a href="http://llvm.cs.uiuc.edu/PR57">[inliner] Inlining invoke with PHI in unwind target is broken</a></li>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]205<li><a href="http://llvm.cs.uiuc.edu/PR58">[linker] linkonce globals should link successfully to external globals</a></li>
Chris Lattnera1a090e2003-10-29 07:17:13 +0000[diff] [blame]206<li><a href="http://llvm.cs.uiuc.edu/PR64">[constmerge] Constant merging pass merges constants with external linkage</a></li>
Chris Lattner5b83b562003-10-29 18:49:14 +0000[diff] [blame]207<li><a href="http://llvm.cs.uiuc.edu/PR66">[scalarrepl] Scalar Replacement of aggregates is decimating structures it shouldn't be</a></li>
Chris Lattnera2bd4e02003-10-30 01:20:42 +0000[diff] [blame]208<li><a href="http://llvm.cs.uiuc.edu/PR70">[instcombine] Resolving invoke inserts cast after terminator</a></li>
Chris Lattnera306dd22003-10-30 01:43:33 +0000[diff] [blame]209<li><a href="http://llvm.cs.uiuc.edu/PR71">llvm-as crashes when labels are used in phi nodes</a></li>
Chris Lattnerb45e1f92003-10-30 16:20:15 +0000[diff] [blame]210<li><a href="http://llvm.cs.uiuc.edu/PR72">[build problem] Callgraph.cpp not pulled in from libipa.a</a></li>
Chris Lattner9dd6a822003-11-16 22:11:42 +0000[diff] [blame]211<li><a href="http://llvm.cs.uiuc.edu/PR77">Variables in scope of output setjmp
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]212calls should be volatile</a> (Note that this does not effect correctness on
213many platforms, such as X86).</li>
Chris Lattneref114d52003-11-03 20:08:08 +0000[diff] [blame]214<li><a href="http://llvm.cs.uiuc.edu/PR83">[X86] Emission of global bool initializers broken</a></li>
Chris Lattnerab77bc52003-11-05 06:30:04 +0000[diff] [blame]215<li><a href="http://llvm.cs.uiuc.edu/PR91">[gccld] The -r (relinking) option does not work correctly</a></li>
Chris Lattner34596d72003-11-07 04:46:56 +0000[diff] [blame]216<li><a href="http://llvm.cs.uiuc.edu/PR92">[bcreader] Cannot read shift constant expressions from bytecode file</a></li>
217<li><a href="http://llvm.cs.uiuc.edu/PR93">[lowersetjmp] Lowersetjmp pass breaks dominance properties!</a></li>
Chris Lattner881cb482003-11-09 19:44:07 +0000[diff] [blame]218<li><a href="http://llvm.cs.uiuc.edu/PR95">SymbolTable::getUniqueName is very inefficient</a></li>
Brian Gaeke4c563b82003-12-11 04:40:58 +0000[diff] [blame]219<li><a href="http://llvm.cs.uiuc.edu/PR97">bugpoint must not pass -R&lt;directory&gt; to Mach-O linker</a></li>
Chris Lattner34596d72003-11-07 04:46:56 +0000[diff] [blame]220<li><a href="http://llvm.cs.uiuc.edu/PR98">[buildscripts] Building into objdir with .o in it fails</a></li>
Chris Lattner699a58d2003-11-08 05:18:50 +0000[diff] [blame]221<li><a href="http://llvm.cs.uiuc.edu/PR101">[setjmp/longjmp] Linking C programs which use setjmp/longjmp sometimes fail with references to the C++ runtime library!</a></li>
Chris Lattnera7235372003-11-12 04:42:37 +0000[diff] [blame]222<li><a href="http://llvm.cs.uiuc.edu/PR107">AsmParser Misses Symbol Redefinition Error</a></li>
Brian Gaeke7aeb2b72003-11-11 21:52:34 +0000[diff] [blame]223<li><a href="http://llvm.cs.uiuc.edu/PR108">gccld -Lfoo -lfoo fails to find ./foo/libfoo.a</a></li>
Chris Lattner7c04a292003-11-14 06:42:01 +0000[diff] [blame]224<li><a href="http://llvm.cs.uiuc.edu/PR110">[bcreader] Incorrect cast causes misread forward constant references</a></li>
Chris Lattner2f486b82003-11-16 21:42:48 +0000[diff] [blame]225<li><a href="http://llvm.cs.uiuc.edu/PR116">[adce] ADCE considers blocks without postdominators to be unreachable</a></li>
Chris Lattnercf40b3f2003-11-18 23:04:02 +0000[diff] [blame]226<li><a href="http://llvm.cs.uiuc.edu/PR123">[X86] div and rem constant exprs invalidate iterators!</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]227<li><a href="http://llvm.cs.uiuc.edu/PR130">[vmcore] Symbol table doesn't rename colliding variables during type resolution</a></li>
Brian Gaeke4c563b82003-12-11 04:40:58 +0000[diff] [blame]228<li><a href="http://llvm.cs.uiuc.edu/PR138">Archive reader does not understand 4.4BSD/Mac OS X long filenames</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]229<li><a href="http://llvm.cs.uiuc.edu/PR140">gccld produces a runner script that includes command-line options to load the necessary shared objects</a></li>
230</ol>
231
232
233<p>Bugs in the C/C++ front-end:</p>
234
235<ol>
236<li><a href="http://llvm.cs.uiuc.edu/PR59">C++ frontend can crash when compiling virtual base classes</a></li>
237<li><a href="http://llvm.cs.uiuc.edu/PR62">C backend fails on constant cast expr to ptr-to-anonymous struct</a></li>
238<li><a href="http://llvm.cs.uiuc.edu/PR63">#ident is not recognized by C frontend</a></li>
239<li><a href="http://llvm.cs.uiuc.edu/PR65">C front-end miscompiles the builtin_expect intrinsic!</a></li>
240<li><a href="http://llvm.cs.uiuc.edu/PR67">1.0 precompiled libstdc++ does not include wchar_t support</a></li>
241<li><a href="http://llvm.cs.uiuc.edu/PR68">llvmgcc asserts when compiling functions renamed with asm's</a></li>
242<li><a href="http://llvm.cs.uiuc.edu/PR69">C frontend crashes on some programs with lots of types.</a></li>
243<li><a href="http://llvm.cs.uiuc.edu/PR79">llvm-gcc crashes compiling global union initializer</a></li>
244<li><a href="http://llvm.cs.uiuc.edu/PR80">C front-end crash on empty structure</a></li>
245<li><a href="http://llvm.cs.uiuc.edu/PR81">CFrontend crashes when compiling C99 compound expressions</a></li>
246<li><a href="http://llvm.cs.uiuc.edu/PR87">llvm-gcc infinite loops on "case MAXINT:"</a></li>
247<li><a href="http://llvm.cs.uiuc.edu/PR89">[C++] Catch blocks make unparsable labels</a></li>
248<li><a href="http://llvm.cs.uiuc.edu/PR90">[C++] Initializing array with constructable objects fail</a></li>
249<li><a href="http://llvm.cs.uiuc.edu/PR94">llvm-gcc tries to add bools</a></li>
250<li><a href="http://llvm.cs.uiuc.edu/PR104">[c++] C++ Frontend lays out superclasses like anonymous bitfields!</a></li>
251<li><a href="http://llvm.cs.uiuc.edu/PR54">C front-end miscompiles unsigned enums whose LLVM types are signed</a></li>
252<li><a href="http://llvm.cs.uiuc.edu/PR112">Casting a string constant to void crashes llvm-gcc</a></li>
Chris Lattnercf40b3f2003-11-18 23:04:02 +0000[diff] [blame]253<li><a href="http://llvm.cs.uiuc.edu/PR125">[llvmg++] Enum types are incorrectly shrunk to smaller than 'int' size</a></li>
254<li><a href="http://llvm.cs.uiuc.edu/PR128">[llvmg++] Cannot use pointer to member to initialize global</a></li>
Chris Lattner983c6672003-11-19 01:08:24 +0000[diff] [blame]255<li><a href="http://llvm.cs.uiuc.edu/PR131">[llvm-gcc] ?: operator as lvalue not implemented</a></li>
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]256<li><a href="http://llvm.cs.uiuc.edu/PR133">[C/C++] Bogus warning about taking the address of 'register' variable</a></li>
Chris Lattnerc4fe9722003-11-20 01:07:41 +0000[diff] [blame]257<li><a href="http://llvm.cs.uiuc.edu/PR113">crash assigning into an array in a struct which contains a bitfield</a>.</li>
258<li><a href="http://llvm.cs.uiuc.edu/PR6">Oversized integer bitfields cause crash</a></li>
Chris Lattner0548bc22003-11-26 08:20:34 +0000[diff] [blame]259<li><a href="http://llvm.cs.uiuc.edu/PR141">[llvm-gcc] Bitfields &amp; large array don't mix well</a></li>
Chris Lattner16bbed22003-11-20 19:30:17 +0000[diff] [blame]260<li><a href="http://llvm.cs.uiuc.edu/PR132">[llvm-gcc] Complex division is not supported</a></li>
Chris Lattner5eac2d62003-11-20 20:59:57 +0000[diff] [blame]261<li><a href="http://llvm.cs.uiuc.edu/PR143">[llvm-gcc] Illegal union field reference</a></li>
Chris Lattner83f43a02003-11-25 08:49:12 +0000[diff] [blame]262<li><a href="http://llvm.cs.uiuc.edu/PR148">[llvmg++] Front-end attempts to return structure by value</a></li>
Chris Lattner86d5c1c2003-11-26 01:18:49 +0000[diff] [blame]263<li><a href="http://llvm.cs.uiuc.edu/PR152">[llvmg++] Pointer to member initializers not supported in constructors</a></li>
264<li><a href="http://llvm.cs.uiuc.edu/PR155">[llvm-gcc] crash on union initialization</a></li>
Chris Lattnerb27353c2003-11-26 02:48:00 +0000[diff] [blame]265<li><a href="http://llvm.cs.uiuc.edu/PR124">[llvm-g++] ?: expressions do not run correct number of destructors!</a></li>
Chris Lattner0548bc22003-11-26 08:20:34 +0000[diff] [blame]266<li><a href="http://llvm.cs.uiuc.edu/PR157">[llvm-gcc] Pointer & constant results in invalid shift</a></li>
Chris Lattnerd2a55f302003-12-08 06:33:19 +0000[diff] [blame]267<li><a href="http://llvm.cs.uiuc.edu/PR165">[llvmg++] call through array of pointers to member functions causes assertion</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]268</ol>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]269
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]270</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]271
272<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]273<div class="doc_section">
274 <a name="portability">Portability and Supported Platforms</a>
275</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]276<!-- *********************************************************************** -->
277
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]278<div class="doc_text">
279
280<p>LLVM has been extensively tested on Intel and AMD machines running Red
Chris Lattner14b5d5a2003-11-08 05:22:09 +0000[diff] [blame]281Hat Linux, and Sun UltraSPARC workstations running Solaris 8. Additionally,
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]282LLVM works on Mac OS/X 10.3 and above, but only with the C backend or
283interpreter (no native backend for the PowerPC is available yet).
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]284The core LLVM infrastructure uses "autoconf" for portability, so hopefully we
Chris Lattner14b5d5a2003-11-08 05:22:09 +0000[diff] [blame]285work on more platforms than that. However, it is likely that we
286missed something, and that minor porting is required to get LLVM to work on
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]287new platforms. We welcome portability patches and error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]288
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]289</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]290
291<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]292<div class="doc_section">
293 <a name="knownproblems">Known Problems</a>
294</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]295<!-- *********************************************************************** -->
296
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]297<div class="doc_text">
298
299<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]300component. As new problems are discovered, they will be added to these
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]301sections.</p>
Chris Lattner3d482502003-10-02 04:57:28 +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
305<!-- _______________________________________________________________________ -->
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]306<!--
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]307</ul><h4><a name="portability"><hr size=0>Portability Problems</h4><ul>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]308-->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]309
310
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]311<!-- ======================================================================= -->
312<div class="doc_subsection">
313 <a name="core">Known problems with the LLVM Core</a>
314</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]315
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]316<div class="doc_text">
317
318<ul>
319
320<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
321work.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]322
323<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]324such, execution of a threaded program could cause these data structures to be
325corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]326
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]327<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]328
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]329<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]330table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]331
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]332<li><a href="http://llvm.cs.uiuc.edu/PR82">LLVM cannot handle structures with
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]333more than 256 elements</a>.</li>
334
335</ul>
336
337</div>
338
339<!-- ======================================================================= -->
340<div class="doc_subsection">
341 <a name="c-fe">Known problems with the C front-end</a>
342</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]343
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]344<!-- _______________________________________________________________________ -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]345<div class="doc_subsubsection">
346 Bugs
347</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]348
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]349<div class="doc_text">
350
351<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]352
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]353<li>C99 Variable sized arrays do not release stack memory when they go out of
354 scope. Thus, the following program may run out of stack space:
355<pre>
356 for (i = 0; i != 1000000; ++i) {
357 int X[n];
358 foo(X);
359 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]360</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]361
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]362</ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]363
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]364</div>
365
366<!-- _______________________________________________________________________ -->
367<div class="doc_subsubsection">
368 Notes
369</div>
370
371<div class="doc_text">
372
373<ul>
374
375<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]376
377<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]378support for floating point data types of any size other than 32 and 64
379bits.</li>
380
381<li>The following Unix system functionality has not been tested and may not
382work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]383 <ol>
384 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
385 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
386 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
387 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
388 - These functions have not been tested.
389 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]390
391<li>Although many GCC extensions are supported, some are not. In particular,
392 the following extensions are known to <b>not be</b> supported:
393 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]394 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
395 <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>
396 <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>
397 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
398 <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>
399 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands</li>
400 <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>
401 <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>
402 <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>
403 <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>
404 <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>
405 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
406 <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]407 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]408
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]409 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]410 attribute means that the LLVM compiler ignores the presence of the attribute,
411 but the code should still work. An unsupported attribute is one which is
412 ignored by the LLVM compiler, which will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]413 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]414
415 <ol>
416 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
417 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]418 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]419
420 <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]421
422 Declaring that functions have no side effects, or that they can never
423 return.<br>
424
425 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
426 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
427 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
428
429 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
430 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
431 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
432
433 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
434 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
435 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]436
437 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
438 Specifying attributes of variables.<br>
439 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
440 <tt>deprecated</tt>, <tt>transparent_union</tt>,
441 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]442
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]443 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
444 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
445 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]446 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]447
448 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.
449 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
450 <tt>deprecated</tt>, <tt>may_alias</tt>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]451
452 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
453 all target specific attributes.</li>
454
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]455 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
456 Other built-in functions.<br>
457 We support all builtins which have a C language equivalent (e.g.,
458 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
459 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]460 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]461
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]462 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]463
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]464 <p>The following extensions <b>are</b> known to be supported:</p>
465
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]466 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]467 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
468 <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>
469 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
470 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
471 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
472 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
473 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
474 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
475 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
476 <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>
477 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
478 <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>
479 <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>
480 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
481 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions or arrays as values.</li>
482 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
483 <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>
484 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
485 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
486 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
487 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
488 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
489 <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>
490 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
491 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
492 <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>
493 <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>
494 <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>
495 <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>
496 <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]497 </ol></li>
498
499</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]500
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]501<p>If you run into GCC extensions which have not been included in any of these
502lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]503
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]504</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]505
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]506<!-- ======================================================================= -->
507<div class="doc_subsection">
508 <a name="c++-fe">Known problems with the C++ front-end</a>
509</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]510
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]511<div class="doc_text">
512
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]513<p>For this release, the C++ front-end is considered to be fully functional, but
514has not been tested as thoroughly as the C front-end. It has been tested and
515works for a number of non-trivial programs, but there may be lurking bugs.
516Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]517
518</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]519
520<!-- _______________________________________________________________________ -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]521<div class="doc_subsubsection">
522 Bugs
523</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]524
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]525<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]526
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]527<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]528<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]529 front-end</a></li>
530</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]531
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]532</div>
533
534<!-- _______________________________________________________________________ -->
535<div class="doc_subsubsection">
536 Notes
537</div>
538
539<div class="doc_text">
540
541<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]542
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]543<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
544parser is significantly more standards compliant (and picky) than prior GCC
545versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame^]546href="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]547
548<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]549 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]550 function and in the <tt>setjmp</tt> receiver function may not be run.
551 Objects in intervening stack frames will be destroyed however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]552 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]553
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]554<li>The LLVM C++ front-end follows the <a
555 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
556 This document, which is not Itanium specific, specifies a standard for name
557 mangling, class layout, v-table layout, RTTI formats, and other C++
558 representation issues. Because we use this API, code generated by the LLVM
559 compilers should be binary compatible with machine code generated by other
560 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
561 <i>However</i>, the exception handling mechanism used by LLVM is very
562 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]563 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]564
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]565</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]566
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]567</div>
568
569<!-- ======================================================================= -->
570<div class="doc_subsection">
571 <a name="x86-be">Known problems with the X86 back-end</a>
572</div>
573
574<div class="doc_text">
575
576<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]577
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]578<li>The X86 code generator <a
Chris Lattnerc4788bb2003-10-08 06:01:38 +0000[diff] [blame]579href="http://llvm.cs.uiuc.edu/PR16">does not currently
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]580support the <tt>unwind</tt> instruction</a>, so code that throws a C++ exception
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]581or calls the C <tt>longjmp</tt> function will abort.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]582
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]583</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]584
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]585</div>
586
587<!-- ======================================================================= -->
588<div class="doc_subsection">
589 <a name="sparc-be">Known problems with the Sparc back-end</a>
590</div>
591
592<div class="doc_text">
593
594<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]595
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]596<li>The Sparc code generator <a
Chris Lattnerc4788bb2003-10-08 06:01:38 +0000[diff] [blame]597href="http://llvm.cs.uiuc.edu/PR15">does not currently
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]598support the <tt>unwind</tt> instruction</a>, so code that throws a C++ exception
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]599or calls the C <tt>longjmp</tt> function will abort.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]600
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]601</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]602
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]603</div>
604
605<!-- ======================================================================= -->
606<div class="doc_subsection">
607 <a name="c-be">Known problems with the C back-end</a>
608</div>
609
610<div class="doc_text">
611
612<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]613
614<li>The C back-end produces code that violates the ANSI C Type-Based Alias
615Analysis rules. As such, special options may be necessary to compile the code
616(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]617problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]618
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]619<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]620cannot include special floating point numbers like Not-A-Number or
621Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]622
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]623<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]624supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]625frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]626
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]627</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]628
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]629</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]630
631<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]632<div class="doc_section">
633 <a name="additionalinfo">Additional Information</a>
634</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]635<!-- *********************************************************************** -->
636
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]637<div class="doc_text">
638
639<p>A wide variety of additional information is available on the LLVM web page,
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]640including mailing lists publications describing algorithms and components
641implemented in LLVM. The web page also contains versions of the API
642documentation which is up-to-date with the CVS version of the source code. You
643can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]644the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]645
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]646<p>If you have any questions or comments about LLVM, please feel free to contact
647us via the mailing lists.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]648
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]649</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]650
651<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]652
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]653<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]654<address>
655 <a href="http://jigsaw.w3.org/css-validator/"><img
656 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
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659
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]660 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]661 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]662</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]663
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]664</body>
665</html>