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gerrit-public.fairphone.software / toolchain / llvm-project / 96be650984ba0136559dece688fb01e157bf6b91 / . / llvm / docs / ReleaseNotes.html
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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
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]58<p>Note that if you are reading this file from CVS, that this document applies
59to the <i>next</i> release, not the previous one. To see the release notes for
60the previous release, see the <a
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
74release implements the following new features:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]75
76<ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]77<li><a
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]78href="http://mail.cs.uiuc.edu/pipermail/llvmdev/2003-November/000528.html">A new
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]79LLVM profiler, similar to gprof</a> is available</li>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]80
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]81<li>LLVM and the C/C++ front-end now compile on Mac OSX! Mac OSX users can
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]82now explore the LLVM optimizer with the C backend (note that LLVM requires GCC
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]833.3 on Mac OSX).</li>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]84
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]85<li>LLVM has been <a
Chris Lattner74a22992003-11-11 23:46:35 +0000[diff] [blame]86href="http://mail.cs.uiuc.edu/pipermail/llvmdev/2003-November/000554.html">moved
87into an 'llvm' C++ namespace</a>, for easier integration with third-party
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]88code. Note that due to a bug in GDB 5.x, to debug namespacified LLVM code,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]89you will need to upgrade to GDB 6.</li>
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]90</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]91
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]92<p>In this release, the following missing features were implemented:</p>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]93
94<ol>
95<li><a href="http://llvm.cs.uiuc.edu/PR88">The interpreter does not support
96invoke or unwind</a></li>
Misha Brukman133b35e2003-11-14 03:30:43 +0000[diff] [blame]97
98<li><a href="http://llvm.cs.uiuc.edu/PR99">Interpreter does not support the
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]99<tt>vaarg</tt> instruction</a></li>
Misha Brukman133b35e2003-11-14 03:30:43 +0000[diff] [blame]100
Brian Gaekec5961312003-11-16 23:49:26 +0000[diff] [blame]101<li><a href="http://llvm.cs.uiuc.edu/PR117">llvm-nm cannot read archive
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]102files</a></li>
Brian Gaekec5961312003-11-16 23:49:26 +0000[diff] [blame]103
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]104</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]105
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]106<p>In this release, the following Quality of Implementation issues were
107fixed:</p>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]108
109<ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]110
111<li><a href="http://llvm.cs.uiuc.edu/PR29">C++ front-end is not generating
112linkonce linkage type when it can</a></li>
113
114<li><a href="http://llvm.cs.uiuc.edu/PR84">C front-end doesn't emit
115getelementptr for address of array element</a></li>
116
Chris Lattnerb2e4d6d2003-11-16 20:25:24 +0000[diff] [blame]117<li><a href="http://llvm.cs.uiuc.edu/PR96">Bad path to the C/C++ frontend causes
118build problems</a></li>
119
120<li><a href="http://llvm.cs.uiuc.edu/PR114">LLVM header files should be -Wold-style-cast clean</a></li>
121
Chris Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]122<li>The LLVM bytecode reader has been <a
123href="http://llvm.cs.uiuc.edu/PR127">sped up a lot</a> (up to 4x in some
124cases).</li>
125
Chris Lattner3a9b2322003-11-22 01:14:58 +0000[diff] [blame]126<li>Methods and functions in anonymous namespaces <a href="http://llvm.cs.uiuc.edu/PR85">now get internal linkage</a>.</li>
127
Chris Lattner0548bc22003-11-26 08:20:34 +0000[diff] [blame]128<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>
129
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]130</ol>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]131
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]132<p>In this release, the following bugs in the previous release were fixed:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]133
134<ol>
Chris Lattner25fd5c12003-10-27 05:41:39 +0000[diff] [blame]135<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]136<li><a href="http://llvm.cs.uiuc.edu/PR58">[linker] linkonce globals should link successfully to external globals</a></li>
Chris Lattnerd16d9752003-10-27 17:58:57 +0000[diff] [blame]137<li><a href="http://llvm.cs.uiuc.edu/PR59">C++ frontend can crash when compiling virtual base classes</a></li>
Chris Lattner36213c72003-10-28 23:13:03 +0000[diff] [blame]138<li><a href="http://llvm.cs.uiuc.edu/PR62">C backend fails on constant cast expr to ptr-to-anonymous struct</a></li>
Chris Lattner56df0a52003-10-29 01:26:07 +0000[diff] [blame]139<li><a href="http://llvm.cs.uiuc.edu/PR63">#ident is not recognized by C frontend</a></li>
Chris Lattnera1a090e2003-10-29 07:17:13 +0000[diff] [blame]140<li><a href="http://llvm.cs.uiuc.edu/PR64">[constmerge] Constant merging pass merges constants with external linkage</a></li>
141<li><a href="http://llvm.cs.uiuc.edu/PR65">C front-end miscompiles the builtin_expect intrinsic!</a></li>
Chris Lattner5b83b562003-10-29 18:49:14 +0000[diff] [blame]142<li><a href="http://llvm.cs.uiuc.edu/PR66">[scalarrepl] Scalar Replacement of aggregates is decimating structures it shouldn't be</a></li>
143<li><a href="http://llvm.cs.uiuc.edu/PR67">1.0 precompiled libstdc++ does not include wchar_t support</a></li>
Chris Lattnerab8873d2003-10-29 20:59:45 +0000[diff] [blame]144<li><a href="http://llvm.cs.uiuc.edu/PR68">llvmgcc asserts when compiling functions renamed with asm's</a></li>
145<li><a href="http://llvm.cs.uiuc.edu/PR69">C frontend crashes on some programs with lots of types.</a></li>
Chris Lattnera2bd4e02003-10-30 01:20:42 +0000[diff] [blame]146<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]147<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]148<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]149<li><a href="http://llvm.cs.uiuc.edu/PR77">Variables in scope of output setjmp
150calls should be volatile</a>. Note that this does not effect correctness on
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]151many platforms, such as X86.</li>
Chris Lattnerdd024a02003-11-02 02:15:11 +0000[diff] [blame]152<li><a href="http://llvm.cs.uiuc.edu/PR79">llvm-gcc crashes compiling global union initializer</a></li>
153<li><a href="http://llvm.cs.uiuc.edu/PR80">C front-end crash on empty structure</a></li>
154<li><a href="http://llvm.cs.uiuc.edu/PR81">CFrontend crashes when compiling C99 compound expressions</a></li>
Chris Lattneref114d52003-11-03 20:08:08 +0000[diff] [blame]155<li><a href="http://llvm.cs.uiuc.edu/PR83">[X86] Emission of global bool initializers broken</a></li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]156<li><a href="http://llvm.cs.uiuc.edu/PR87">llvm-gcc infinite loops on "case MAXINT:"</a></li>
Chris Lattnerab77bc52003-11-05 06:30:04 +0000[diff] [blame]157<li><a href="http://llvm.cs.uiuc.edu/PR89">[C++] Catch blocks make unparsable labels</a></li>
158<li><a href="http://llvm.cs.uiuc.edu/PR90">[C++] Initializing array with constructable objects fail</a></li>
159<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]160<li><a href="http://llvm.cs.uiuc.edu/PR92">[bcreader] Cannot read shift constant expressions from bytecode file</a></li>
161<li><a href="http://llvm.cs.uiuc.edu/PR93">[lowersetjmp] Lowersetjmp pass breaks dominance properties!</a></li>
162<li><a href="http://llvm.cs.uiuc.edu/PR94">llvm-gcc tries to add bools</a></li>
Chris Lattner881cb482003-11-09 19:44:07 +0000[diff] [blame]163<li><a href="http://llvm.cs.uiuc.edu/PR95">SymbolTable::getUniqueName is very inefficient</a></li>
Chris Lattner34596d72003-11-07 04:46:56 +0000[diff] [blame]164<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]165<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 Lattner881cb482003-11-09 19:44:07 +0000[diff] [blame]166<li><a href="http://llvm.cs.uiuc.edu/PR104">[c++] C++ Frontend lays out superclasses like anonymous bitfields!</a></li>
Chris Lattnera7235372003-11-12 04:42:37 +0000[diff] [blame]167<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]168<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]169<li><a href="http://llvm.cs.uiuc.edu/PR110">[bcreader] Incorrect cast causes misread forward constant references</a></li>
Brian Gaekeb8b238b2003-11-12 22:48:52 +0000[diff] [blame]170<li><a href="http://llvm.cs.uiuc.edu/PR112">Casting a string constant to void crashes llvm-gcc</a></li>
Chris Lattner2f486b82003-11-16 21:42:48 +0000[diff] [blame]171<li><a href="http://llvm.cs.uiuc.edu/PR116">[adce] ADCE considers blocks without postdominators to be unreachable</a></li>
Chris Lattner37d449d2003-11-18 06:25:05 +0000[diff] [blame]172<li><a href="http://llvm.cs.uiuc.edu/PR54">C front-end miscompiles unsigned enums whose LLVM types are signed</a></li>
Chris Lattnercf40b3f2003-11-18 23:04:02 +0000[diff] [blame]173<li><a href="http://llvm.cs.uiuc.edu/PR123">[X86] div and rem constant exprs invalidate iterators!</a></li>
174<li><a href="http://llvm.cs.uiuc.edu/PR125">[llvmg++] Enum types are incorrectly shrunk to smaller than 'int' size</a></li>
175<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]176<li><a href="http://llvm.cs.uiuc.edu/PR130">[vmcore] Symbol table doesn't rename colliding variables during type resolution</a></li>
177<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]178<li><a href="http://llvm.cs.uiuc.edu/PR133">[C/C++] Bogus warning about taking the address of 'register' variable</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]179<li><a href="http://llvm.cs.uiuc.edu/PR97">bugpoint must not pass -R&lt;directory&gt; to Mach-O linker</a></li>
Chris Lattnerc4fe9722003-11-20 01:07:41 +0000[diff] [blame]180<li><a href="http://llvm.cs.uiuc.edu/PR113">crash assigning into an array in a struct which contains a bitfield</a>.</li>
181<li><a href="http://llvm.cs.uiuc.edu/PR6">Oversized integer bitfields cause crash</a></li>
Misha Brukmanffec0b72003-11-21 22:11:12 +0000[diff] [blame]182<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>
Chris Lattner0548bc22003-11-26 08:20:34 +0000[diff] [blame]183<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]184<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]185<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]186<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]187<li><a href="http://llvm.cs.uiuc.edu/PR152">[llvmg++] Pointer to member initializers not supported in constructors</a></li>
188<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]189<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]190<li><a href="http://llvm.cs.uiuc.edu/PR157">[llvm-gcc] Pointer & constant results in invalid shift</a></li>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]191</ol><p>
192
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]193<p>At this time, LLVM is known to work properly with SPEC CPU 2000 (X86 only),
194the Olden benchmarks, and the Ptrdist benchmarks among many other programs.
195Note however that the Sparc and X86 backends do not currently support exception
196throwing or long jumping (including 253.perlbmk in SPEC). For these programs,
197you must use the C backend.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]198
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]199</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]200
201<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]202<div class="doc_section">
203 <a name="portability">Portability and Supported Platforms</a>
204</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]205<!-- *********************************************************************** -->
206
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]207<div class="doc_text">
208
209<p>LLVM has been extensively tested on Intel and AMD machines running Red
Chris Lattner14b5d5a2003-11-08 05:22:09 +0000[diff] [blame]210Hat Linux, and Sun UltraSPARC workstations running Solaris 8. Additionally,
211LLVM works on Mac OS/X 10.3 and above, but only with the C back-end (no native
212backend for the PowerPC is available yet).
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]213The core LLVM infrastructure uses "autoconf" for portability, so hopefully we
Chris Lattner14b5d5a2003-11-08 05:22:09 +0000[diff] [blame]214work on more platforms than that. However, it is likely that we
215missed something, and that minor porting is required to get LLVM to work on
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]216new platforms. We welcome portability patches and error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]217
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]218</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]219
220<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]221<div class="doc_section">
222 <a name="knownproblems">Known Problems</a>
223</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]224<!-- *********************************************************************** -->
225
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]226<div class="doc_text">
227
228<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]229component. As new problems are discovered, they will be added to these
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]230sections.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]231
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]232</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]233
234<!-- _______________________________________________________________________ -->
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]235<!--
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]236</ul><h4><a name="portability"><hr size=0>Portability Problems</h4><ul>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]237-->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]238
239
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]240<!-- ======================================================================= -->
241<div class="doc_subsection">
242 <a name="core">Known problems with the LLVM Core</a>
243</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]244
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]245<div class="doc_text">
246
247<ul>
248
249<li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not
250work.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]251
252<li>The JIT does not use mutexes to protect its internal data structures. As
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]253such, execution of a threaded program could cause these data structures to be
254corrupted.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]255
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]256<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]257
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]258<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]259table in the archive).</li>
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]260
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]261<li><a href="http://llvm.cs.uiuc.edu/PR82">LLVM cannot handle structures with
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]262more than 256 elements</a>.</li>
263
264</ul>
265
266</div>
267
268<!-- ======================================================================= -->
269<div class="doc_subsection">
270 <a name="c-fe">Known problems with the C front-end</a>
271</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]272
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]273<!-- _______________________________________________________________________ -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]274<div class="doc_subsubsection">
275 Bugs
276</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]277
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]278<div class="doc_text">
279
280<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]281
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]282<li>C99 Variable sized arrays do not release stack memory when they go out of
283 scope. Thus, the following program may run out of stack space:
284<pre>
285 for (i = 0; i != 1000000; ++i) {
286 int X[n];
287 foo(X);
288 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]289</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]290
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]291</ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]292
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]293</div>
294
295<!-- _______________________________________________________________________ -->
296<div class="doc_subsubsection">
297 Notes
298</div>
299
300<div class="doc_text">
301
302<ul>
303
304<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]305
306<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]307support for floating point data types of any size other than 32 and 64
308bits.</li>
309
310<li>The following Unix system functionality has not been tested and may not
311work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]312 <ol>
313 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
314 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
315 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
316 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
317 - These functions have not been tested.
318 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]319
320<li>Although many GCC extensions are supported, some are not. In particular,
321 the following extensions are known to <b>not be</b> supported:
322 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]323 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
324 <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>
325 <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>
326 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
327 <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>
328 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands</li>
329 <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>
330 <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>
331 <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>
332 <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>
333 <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>
334 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
335 <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]336 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]337
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]338 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]339 attribute means that the LLVM compiler ignores the presence of the attribute,
340 but the code should still work. An unsupported attribute is one which is
341 ignored by the LLVM compiler, which will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]342 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]343
344 <ol>
345 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
346 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]347 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]348
349 <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]350
351 Declaring that functions have no side effects, or that they can never
352 return.<br>
353
354 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
355 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
356 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
357
358 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
359 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
360 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
361
362 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
363 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
364 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]365
366 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
367 Specifying attributes of variables.<br>
368 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
369 <tt>deprecated</tt>, <tt>transparent_union</tt>,
370 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]371
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]372 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
373 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
374 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]375 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]376
377 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.
378 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
379 <tt>deprecated</tt>, <tt>may_alias</tt>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]380
381 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
382 all target specific attributes.</li>
383
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]384 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
385 Other built-in functions.<br>
386 We support all builtins which have a C language equivalent (e.g.,
387 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
388 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]389 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt> (ignored).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]390
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]391 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]392
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]393 <p>The following extensions <b>are</b> known to be supported:</p>
394
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]395 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]396 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
397 <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>
398 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
399 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
400 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
401 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
402 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
403 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
404 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
405 <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>
406 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
407 <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>
408 <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>
409 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
410 <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>
411 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
412 <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>
413 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
414 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
415 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
416 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
417 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
418 <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>
419 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
420 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
421 <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>
422 <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>
423 <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>
424 <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>
425 <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]426 </ol></li>
427
428</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]429
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]430<p>If you run into GCC extensions which have not been included in any of these
431lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]432
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]433</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]434
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]435<!-- ======================================================================= -->
436<div class="doc_subsection">
437 <a name="c++-fe">Known problems with the C++ front-end</a>
438</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]439
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]440<div class="doc_text">
441
442<p>For this release, the C++ front-end is considered to be fully functional but
443of <b>beta</b> quality. It has been tested and works for a number of simple
444programs that collectively exercise most of the language. Nevertheless, it has
445not been in use as long as the C front-end. Please report any bugs or
446problems.</p>
447
448</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]449
450<!-- _______________________________________________________________________ -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]451<div class="doc_subsubsection">
452 Bugs
453</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]454
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]455<div class="doc_text">
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]456
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]457<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]458<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]459 front-end</a></li>
460</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]461
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]462</div>
463
464<!-- _______________________________________________________________________ -->
465<div class="doc_subsubsection">
466 Notes
467</div>
468
469<div class="doc_text">
470
471<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]472
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]473<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
474parser is significantly more standards compliant (and picky) than prior GCC
475versions. For more information, see the C++ section of the <a
476href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.<p>
477
478<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]479 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]480 function and in the <tt>setjmp</tt> receiver function may not be run.
481 Objects in intervening stack frames will be destroyed however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]482 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]483
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]484<li>The LLVM C++ front-end follows the <a
485 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
486 This document, which is not Itanium specific, specifies a standard for name
487 mangling, class layout, v-table layout, RTTI formats, and other C++
488 representation issues. Because we use this API, code generated by the LLVM
489 compilers should be binary compatible with machine code generated by other
490 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
491 <i>However</i>, the exception handling mechanism used by LLVM is very
492 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]493 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]494
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]495<li><a href="http://llvm.cs.uiuc.edu/PR11">Code for executing destructors when
496 unwinding is not shared</a> (this is a quality of implementation problem,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]497 which does not effect functionality).</li>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]498
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]499</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]500
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]501</div>
502
503<!-- ======================================================================= -->
504<div class="doc_subsection">
505 <a name="x86-be">Known problems with the X86 back-end</a>
506</div>
507
508<div class="doc_text">
509
510<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]511
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]512<li>The X86 code generator <a
Chris Lattnerc4788bb2003-10-08 06:01:38 +0000[diff] [blame]513href="http://llvm.cs.uiuc.edu/PR16">does not currently
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]514support the <tt>unwind</tt> instruction</a>, so code that throws a C++ exception
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]515or calls the C <tt>longjmp</tt> function will abort.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]516
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]517</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]518
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]519</div>
520
521<!-- ======================================================================= -->
522<div class="doc_subsection">
523 <a name="sparc-be">Known problems with the Sparc back-end</a>
524</div>
525
526<div class="doc_text">
527
528<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]529
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]530<li>The Sparc code generator <a
Chris Lattnerc4788bb2003-10-08 06:01:38 +0000[diff] [blame]531href="http://llvm.cs.uiuc.edu/PR15">does not currently
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]532support the <tt>unwind</tt> instruction</a>, so code that throws a C++ exception
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]533or calls the C <tt>longjmp</tt> function will abort.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]534
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]535</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]536
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]537</div>
538
539<!-- ======================================================================= -->
540<div class="doc_subsection">
541 <a name="c-be">Known problems with the C back-end</a>
542</div>
543
544<div class="doc_text">
545
546<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]547
548<li>The C back-end produces code that violates the ANSI C Type-Based Alias
549Analysis rules. As such, special options may be necessary to compile the code
550(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]551problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]552
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]553<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]554cannot include special floating point numbers like Not-A-Number or
555Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]556
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]557<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]558supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]559frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]560
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]561<li>The code produces by the C back-end has only been tested with the Sun CC,
562GCC, and Intel compilers. It is possible that it will have to be adjusted to
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]563support other C compilers.</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 Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]566
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]567</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]568
569<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]570<div class="doc_section">
571 <a name="additionalinfo">Additional Information</a>
572</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]573<!-- *********************************************************************** -->
574
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]575<div class="doc_text">
576
577<p>A wide variety of additional information is available on the LLVM web page,
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]578including mailing lists publications describing algorithms and components
579implemented in LLVM. The web page also contains versions of the API
580documentation which is up-to-date with the CVS version of the source code. You
581can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]582the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]583
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]584<p>If you have any questions or comments about LLVM, please feel free to contact
585us via the mailing lists.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]586
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]587</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]588
589<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]590
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]591<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]592<address>
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Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]598 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]599 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]600</address>
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Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]602</body>
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