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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 45de191b0bb337142a3f2a09f5f7410844e46a81 / . / docs / ReleaseNotes.html
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Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
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4<head>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]6 <link rel="stylesheet" href="llvm.css" type="text/css">
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]7 <title>LLVM 1.4 Release Notes</title>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]10
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]11<div class="doc_title">LLVM 1.4 Release Notes</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]12
13<ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]14 <li><a href="#intro">Introduction</a></li>
15 <li><a href="#whatsnew">What's New?</a></li>
Chris Lattner4b538b92004-04-30 22:17:12 +0000[diff] [blame]16 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]18 <li><a href="#knownproblems">Known Problems</a>
19 <ul>
Chris Lattner2974b5b2004-04-01 00:41:31 +0000[diff] [blame]20 <li><a href="#experimental">Experimental features included in this
21 release</a>
Chris Lattner79c3fe12003-10-02 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>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]26 <li><a href="#sparcv9-be">Known problems with the SparcV9 Back-end</a>
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]27 <li><a href="#ppc-be">Known problems with the PowerPC Back-end</a>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]28 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]29 </ul></li>
30 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]31</ol>
32
Chris Lattner7911ce22004-05-23 21:07:27 +0000[diff] [blame]33<div class="doc_author">
34 <p>Written by the <a href="http://llvm.cs.uiuc.edu">LLVM team</a><p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]35</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]36
37<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]38<div class="doc_section">
39 <a name="intro">Introduction</a>
40</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]41<!-- *********************************************************************** -->
42
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]43<div class="doc_text">
44
45<p>This document contains the release notes for the LLVM compiler
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]46infrastructure, release 1.4. Here we describe the status of LLVM, including any
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]47known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]48version of this document can be found on the <a
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]49href="http://llvm.cs.uiuc.edu/releases/1.4/">LLVM 1.4 web site</a>. If you are
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]50not reading this on the LLVM web pages, you should probably go there because
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]51this document may be updated after the release.</p>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]52
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]53<p>For more information about LLVM, including information about potentially more
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]54current releases, please check out the <a href="http://llvm.cs.uiuc.edu">main
55web site</a>. If you have questions or comments, the <a
56href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]57list</a> is a good place to send them.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]58
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]59<p>Note that if you are reading this file from CVS, this document applies
60to the <i>next</i> release, not the current one. To see the release notes for
61the current or previous releases, see the <a
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]62href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
63
64</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]65
66<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]67<div class="doc_section">
68 <a name="whatsnew">What's New?</a>
69</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]70<!-- *********************************************************************** -->
71
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]72<div class="doc_text">
73
Chris Lattner5c3389a2004-08-16 00:20:18 +0000[diff] [blame]74<p>This is the fifth public release of the LLVM compiler infrastructure.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]75
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]76<p> At this time, LLVM is known to correctly compile and run all C &amp; C++
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]77SPEC CPU95 &amp; 2000 benchmarks, the Olden benchmarks, and the Ptrdist
Chris Lattner9b3b04f2004-10-16 18:35:57 +0000[diff] [blame]78benchmarks, and <b>many</b> other C and C++ programs.</p>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]79
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]80</div>
81
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]82<!--=========================================================================-->
83<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]84<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]85</div>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]86
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]87<div class="doc_text">
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]88<ol>
Chris Lattnera4bcecf2004-11-27 19:24:06 +0000[diff] [blame]89 <li>LLVM now includes a JIT for the PowerPC target.</li>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]90 <li>LLVM now optimizes global variables significantly more than it did
91 before.
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]92 </li>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]93 <li>LLVM now includes the new '<tt>undef</tt>' value and
94 <a href="LangRef.html#i_unreachable"><tt>unreachable</tt></a> instruction,
95 which give the optimizer more information about the behavior of the
96 program.
97 </li>
98 <li>llvmgcc and llvmg++ now emit source line number information when '-g' is
99 passed in. This information can be used with llvm-db or other tools and
100 passes.
101 </li>
102 <li>The test/Programs hierarchy <a href="http://llvm.cs.uiuc.edu/PR257">has
103 been moved out of the main LLVM tree</a> into a separate CVS repository and
104 tarball. This shrinks the distribution size of LLVM itself significantly.
105 </li>
106 <li>Bytecode compression with bzip2 has been implemented. All bytecode files
107 generated by LLVM will now be compressed by default. Compression can be
108 disabled with the <tt>-disable-compression</tt> option to the tools that can
109 generate bytecode files.
110 </li>
111 <li>A generic <a href="http://llvm.cs.uiuc.edu/PR353">compiler driver</a> and
112 an associated <a href="CommandGuide/html/llvm-ld.html">generic linker</a> have
113 been implemented. The compiler driver is generic because it can be configured
114 to pre-process, translate, optimize, assemble, and link code from any source
115 language. This aids compiler writers because all that is needed is a
116 source-to-bytecode or source-to-assembly translator and a configuration file.
117 The linker is generic because it allows dynamically loadable optimization
118 modules to be executed for link-time optimization. Language specific
119 link-time optimization modules can be created and executed automatically.
120 </li>
121 <li>The <a href="http://llvm.cs.uiuc.edu/PR263">dependent libraries</a>
122 feature has been implemented. This allows front end compilers to indicate in
123 the bytecode which libraries the bytecode needs to be linked with. Both the
124 C/C++ front end and Stacker support generating the required libraries. The
125 Linker now supports using this information to ensure required libaries are
126 linked into the module. This minimizes the need to use the <tt>-l</tt> option
127 when using <a href="CommandGuide/html/llvmc.html"><tt>llvmc</tt></a>
128 </li>
129 <li>The LLVM makefiles have been improved to build LLVM faster (2x) and
130 includes new targets (like dist-check, uninstall). One important change is
131 associated with <a href="http://llvm.cs.uiuc.edu/PR456">PR456</a>. The
132 libraries and tools will now be built into <tt>$builddir/Debug/{bin,lib}</tt>
133 instead of <tt>$builddir/tools/Debug</tt> and <tt>$builddir/lib/Debug</tt>.
134 Similarly for <tt>Release</tt> and <tt>Profile</tt> builds.
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]135 </li>
Chris Lattner7c8dd7f2004-11-17 18:19:32 +0000[diff] [blame]136 <li>The LLVM source code is much more compatible with Microsoft Visual C++,
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]137 including the JIT and runtime-code generation, though the entire system
138 may not work with it.
139 </li>
Chris Lattnere55cb542004-11-22 22:09:58 +0000[diff] [blame]140 <li>The target-to-JIT interfaces <a href="http://llvm.cs.uiuc.edu/PR283">are
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]141 now much simpler</a> and more powerful.
142 </li>
Chris Lattnera4bcecf2004-11-27 19:24:06 +0000[diff] [blame]143 <li>zlib and libpng are <a href="http://llvm.cs.uiuc.edu/PR417">no longer
144 included in the main LLVM tarball</a>.</li>
Chris Lattner748e58b2004-11-27 19:50:58 +0000[diff] [blame]145 <li>The LLVM code generator now generates asm writers for the target from
146 an abstract target description, instead of requiring them to be hand
147 written.</li>
Chris Lattnerb7c00752004-11-27 21:29:43 +0000[diff] [blame]148 <li>LLVM regression and feature tests can now be run with DejaGNU.</li>
Chris Lattnerd92017a2004-12-01 17:10:36 +0000[diff] [blame]149 <li>llvmgcc and llvmg++ now emit source-level line number information, making
150 it possible to map from LLVM code back to source. This is currently used
151 by llvm-db.</li>
Chris Lattner55ee0312003-11-19 22:05:38 +0000[diff] [blame]152</ol>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]153
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]154</div>
155
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]156
157<!--=========================================================================-->
158<div class="doc_subsubsection">
159In this release, the following missing features were implemented:
160</div>
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]161
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]162<div class="doc_text">
163
Chris Lattner0ef19062003-11-08 04:28:55 +0000[diff] [blame]164<ol>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]165 <li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]166 arbitrary calls</a>
167 </li>
Reid Spencer6454ed32004-11-18 18:38:58 +0000[diff] [blame]168 <li>The <tt>llvm-ar</tt> tool was previously incomplete and didn't properly
169 support other ar(1) implementations. This has been corrected. <tt>llvm-ar</tt>
170 now fully supports all archive editing functions, table of contents listing,
171 extraction, and printing. It can also read BSD4.4/MacOSX and SVR4 style
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]172 archives. See <a href="CommandGuide/html/llvm-ar.html">llvm-ar</a> for
173 details.
174 </li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]175</ol>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]176
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]177</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]178
179<!--=========================================================================-->
180<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]181<a name="qualityofimp">In this release, the following Quality of Implementation
182issues were fixed:</a>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]183</div>
184
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]185<div class="doc_text">
186
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]187<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]188 <li><a href="http://llvm.cs.uiuc.edu/PR426">[llvmg++] Tons of warnings
189 are spewed when linking to libstdc++</a>
190 </li>
191 <li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
192 include/llvm/{Support,Config}</a>
193 </li>
Reid Spencerccbc9cf2004-11-22 18:40:51 +0000[diff] [blame]194 <li>The names of the libraries generated by compiling LLVM source have been
195 changed to ensure they do not conflict with other packages upon installation.
196 Each LLVM library is now prefixed with LLVM and uses mixed clase. For example,
197 the library <tt>libasmparser.a</tt> in 1.3 has become
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]198 <tt>libLLVMAsmParser.a</tt> in release 1.4.
199 </li>
Chris Lattnerc33bf812004-11-27 21:33:28 +0000[diff] [blame]200 <li><a href="http://llvm.cs.uiuc.edu/PR459">[llvmg++] C++ frontend is expanding
201 lots of unused inline functions</a></li>
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]202</ol>
203
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]204</div>
205
Chris Lattnere29ac162003-12-20 03:42:11 +0000[diff] [blame]206<!--=========================================================================-->
207<div class="doc_subsubsection">
Chris Lattnera39719f2004-02-25 16:36:51 +0000[diff] [blame]208In this release, the following build problems were fixed:
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]209</div>
210
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]211<div class="doc_text">
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]212<ol>
Reid Spencer7409d1c2004-11-25 06:07:42 +0000[diff] [blame]213 <li><a href="http://llvm.cs.uiuc.edu/PR256">[autoconf] further standardizing
214 autoconf usage</a>. Various improvements in the configure.ac script were
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]215 made as well as the makefile system.
216 </li>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]217</ol>
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]218</div>
Brian Gaeke6b31beb2004-01-16 21:55:04 +0000[diff] [blame]219
220<!--=========================================================================-->
221<div class="doc_subsubsection">
Chris Lattner6e1ef192004-05-02 04:19:15 +0000[diff] [blame]222<a name="codequality">This release includes the following Code Quality
223improvements:</a>
Chris Lattneraab56d42004-05-23 20:42:08 +0000[diff] [blame]224</div>
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]225
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]226<div class="doc_text">
Chris Lattner89ca2b82003-10-27 17:06:39 +0000[diff] [blame]227<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]228 <li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
229 std::min/std::max</a>
230 </li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]231</ol>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]232</div>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]233
234<!--=========================================================================-->
235<div class="doc_subsubsection">
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]236<a name="bugfix">In this release, the following bugs in the previous release
237were fixed:</a>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]238</div>
239
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]240<div class="doc_text">
241
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]242<p>Bugs fixed in the LLVM Core:</p>
Chris Lattner47ad72c2003-10-07 21:38:31 +0000[diff] [blame]243
244<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]245 <li><a href="http://llvm.cs.uiuc.edu/PR420">[licm] LICM invalidates alias
246 analysis info and uses broken information</a> (optimizer crash)</li>
247 <li><a href="http://llvm.cs.uiuc.edu/PR422">[asmwriter] Asmwriter is really
248 slow for functions with lots of values</a></li>
249 <li><a href="http://llvm.cs.uiuc.edu/PR423">[anders-aa] Andersen's AA is
250 completely broken in LLVM 1.3</a></li>
251 <li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction
252 tables defined</a></li>
253 <li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions
254 w/certain names tickles GNU 'as' bugs</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]255</ol>
256
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]257<p>Bugs in the C/C++ front-end:</p>
258
259<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]260 <li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are
261 instantiated</a></li>
262 <li><a href="http://llvm.cs.uiuc.edu/PR450">[llvmg++] Extern const globals
263 cannot be marked 'constant' if they have nontrivial ctors or dtors</a></li>
264 <li><a href="http://llvm.cs.uiuc.edu/PR461">[llvmgcc] Crash compiling unnamed
Chris Lattner4df69b82004-11-25 06:31:42 +0000[diff] [blame]265 bitfield which does not increase struct size</a></li>
Chris Lattner748e58b2004-11-27 19:50:58 +0000[diff] [blame]266 <li><a href="http://llvm.cs.uiuc.edu/PR424">[llvmgcc] llvmgcc emits invalid
267 constant exprs</a></li>
Chris Lattner0db649c2004-11-27 22:47:08 +0000[diff] [blame]268 <li><a href="http://llvm.cs.uiuc.edu/PR421">[llvmg++] Crash in initializing
269 array with constructors in hard EH situations</a></li>
Chris Lattnereeeff012004-11-27 23:27:26 +0000[diff] [blame]270 <li><a href="http://llvm.cs.uiuc.edu/PR397">[llvm-gcc] Inline function
271 redefinitions error due to 'asm' function rename</a></li>
Chris Lattner87c74b72004-11-28 00:43:59 +0000[diff] [blame]272 <li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an
Chris Lattner9b5d3952004-11-28 00:09:38 +0000[diff] [blame]273 implicitly external function is re-declared as static</a></li>
Chris Lattner87c74b72004-11-28 00:43:59 +0000[diff] [blame]274 <li><a href="http://llvm.cs.uiuc.edu/PR360">[llvmgcc] Structure field with
275 non-constant offset crashes llvmgcc</a></li>
Chris Lattner04cf0c22004-11-28 01:25:20 +0000[diff] [blame]276 <li><a href="http://llvm.cs.uiuc.edu/PR447">[llvmg++] Crash compiling
277 friend with default argument</a></li>
Chris Lattnera5099962003-12-06 20:22:41 +0000[diff] [blame]278</ol>
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]279
280<p>Bugs fixed in the Sparc V9 back-end:</p>
281
282<ol>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]283 <li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaekee77c8e72004-08-24 07:43:48 +0000[diff] [blame]284 failure with certain indirect calls</a></li>
285</ol>
286
Chris Lattner80453c92004-05-24 04:50:25 +0000[diff] [blame]287</div>
Reid Spencer8e0262f2004-05-23 17:23:13 +0000[diff] [blame]288
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]289<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]290<div class="doc_section">
291 <a name="portability">Portability and Supported Platforms</a>
292</div>
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]293<!-- *********************************************************************** -->
294
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]295<div class="doc_text">
296
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]297<p>LLVM is known to work in the following platforms:</p>
298
299<ul>
300<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
301 other unix-like systems).</li>
302<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]303<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattner4f7ac4c2004-11-25 06:33:10 +0000[diff] [blame]304<li>PowerPC-based Mac OS X boxes, running 10.2 and above.</li>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]305</ul>
306
Brian Gaekeb0fd7612004-05-09 05:28:35 +0000[diff] [blame]307<p>The core LLVM infrastructure uses
308<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
309to the machine and operating system on which it is built. However, minor
310porting may be required to get LLVM to work on new platforms. We welcome your
311portability patches and reports of successful builds or error messages.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]312
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]313<p>Note that the LLVM build system does not currently support directories with
314spaces on them when running on Win32/cygwin. We strongly recommend running
315LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattner74032a52004-06-01 19:41:30 +0000[diff] [blame]316<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
317cygwin packages. By default, many important tools are not installed that
Chris Lattner5aff3552004-08-16 20:20:46 +0000[diff] [blame]318are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
319please make sure that there are no directories with spaces in them in your
320PATH environment variable.</p>
Chris Lattner4654bdb2004-06-01 18:22:41 +0000[diff] [blame]321
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]322</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]323
324<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]325<div class="doc_section">
326 <a name="knownproblems">Known Problems</a>
327</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]328<!-- *********************************************************************** -->
329
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]330<div class="doc_text">
331
332<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]333component. As new problems are discovered, they will be added to these
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]334sections. If you run into a problem, please check the <a
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]335href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]336there isn't already one.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]337
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]338</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]339
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]340<!-- ======================================================================= -->
341<div class="doc_subsection">
342 <a name="experimental">Experimental features included with this release</a>
343</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]344
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]345<div class="doc_text">
346
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]347<p>The following components of this LLVM release are either untested, known to
348be broken or unreliable, or are in early development. These components should
349not be relied on, and bugs should not be filed against them, but they may be
350useful to some people. In particular, if you would like to work on one of these
351components, please contact us on the llvmdev list.</p>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]352
353<ul>
354<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner9934f972004-09-14 16:43:13 +0000[diff] [blame]355 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]356<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
357 it should) and not thoroughly tested.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]358<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
Chris Lattner0da7f492004-12-02 17:20:17 +0000[diff] [blame]359<li>The "iterative scan" register allocator (enabled with -regalloc=iterativescan)
360 is not stable.</li>
Chris Lattnerf5ee1702004-03-14 02:03:02 +0000[diff] [blame]361</ul>
362
363</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]364
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]365<!-- ======================================================================= -->
366<div class="doc_subsection">
367 <a name="core">Known problems with the LLVM Core</a>
368</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]369
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]370<div class="doc_text">
371
372<ul>
Reid Spencer4f86f9c2004-11-25 22:38:30 +0000[diff] [blame]373 <li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not work.
374 </li>
375 <li>The JIT does not use mutexes to protect its internal data structures. As
376 such, execution of a threaded program could cause these data structures to be
377 corrupted.
378 </li>
379 <li>Linking in static archive files (.a files) is slow by default because
380 there is no symbol table in the archive. To remedy this, run
381 <a href="CommandGuide/html/llvm-ranlib.html"><tt>llvm-ranlib</tt></a> on the
382 archive to add an LLVM symbol table.
383 </li>
384 <li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
385 objects/archives in the order specified on the command line.</a>
386 </li>
387 <li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not
388 mark values live across a setjmp as volatile</a>. This missing feature
389 only affects targets whose setjmp/longjmp libraries do not save and restore
390 the entire register file.</li>
Reid Spencer043e4b12004-11-25 22:43:58 +0000[diff] [blame]391 <li><a href="http://llvm.cs.uiuc.edu/PR427">[bytecode] Assertion on V1
392 Bytecode Files</a>. This bug won't be fixed because V1 bytecode had its own
393 problems, no one is using V1 bytecode any more, and the fix is non-trivial.
394 </li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]395</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]396</div>
397
398<!-- ======================================================================= -->
399<div class="doc_subsection">
400 <a name="c-fe">Known problems with the C front-end</a>
401</div>
Chris Lattner47588f92003-10-02 05:07:23 +0000[diff] [blame]402
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]403<!-- _______________________________________________________________________ -->
Chris Lattnerb40efb32003-12-14 05:03:43 +0000[diff] [blame]404<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]405
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]406<div class="doc_text">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]407<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]408<li>C99 Variable sized arrays do not release stack memory when they go out of
409 scope. Thus, the following program may run out of stack space:
410<pre>
411 for (i = 0; i != 1000000; ++i) {
412 int X[n];
413 foo(X);
414 }
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]415</pre></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]416
Misha Brukman6df9e2c2004-05-12 21:46:05 +0000[diff] [blame]417<li>Initialization of global union variables can only be done <a
418href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
419member</a>.</li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]420
Misha Brukmana7aadf12004-04-19 02:56:49 +0000[diff] [blame]421<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
422external function is re-declared as static</a></li>
Chris Lattnerf580cdc2004-03-16 21:39:04 +0000[diff] [blame]423
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]424</ul>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]425</div>
426
427<!-- _______________________________________________________________________ -->
428<div class="doc_subsubsection">
429 Notes
430</div>
431
432<div class="doc_text">
433
434<ul>
435
436<li>Inline assembly is not yet supported.</li>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]437
438<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]439support for floating point data types of any size other than 32 and 64
440bits.</li>
441
442<li>The following Unix system functionality has not been tested and may not
443work:
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]444 <ol>
445 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
446 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
447 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
448 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
449 - These functions have not been tested.
450 </ol></li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]451
452<li>Although many GCC extensions are supported, some are not. In particular,
453 the following extensions are known to <b>not be</b> supported:
454 <ol>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]455 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]456 <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>
457 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
458 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Extended%20Asm">Extended Asm</a>: Assembler instructions with C expressions as operands.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]459 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]460 <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>
461 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Explicit-Reg-Vars.html#Explicit%20Reg%20Vars">Explicit Reg Vars</a>: Defining variables residing in specified registers.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]462 <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>
463 <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>
464 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
465 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pragmas.html#Pragmas">Pragmas</a>: Pragmas accepted by GCC.</li>
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]466 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]467
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]468 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]469 attribute means that the LLVM compiler ignores the presence of the attribute,
470 but the code should still work. An unsupported attribute is one which is
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]471 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]472 the program.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]473
474 <ol>
475 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
476 Arrays whose length is computed at run time.<br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]477 Supported, but allocated stack space is not freed until the function returns (noted above).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]478
479 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Attributes.html#Function%20Attributes">Function Attributes</a>:
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]480
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]481 Declaring that functions have no side effects or that they can never
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]482 return.<br>
483
484 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
485 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
486 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
487
488 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
489 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
490 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
491
492 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
493 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
494 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]495
496 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
497 Specifying attributes of variables.<br>
498 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
499 <tt>deprecated</tt>, <tt>transparent_union</tt>,
500 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]501
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]502 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
503 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
504 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]505 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]506
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]507 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.<br>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]508 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]509 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]510
511 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
512 all target specific attributes.</li>
513
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]514 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
515 Other built-in functions.<br>
516 We support all builtins which have a C language equivalent (e.g.,
517 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
518 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerceebeb62004-06-18 06:26:29 +0000[diff] [blame]519 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
520 (currently ignored). We also support builtins for ISO C99 floating
521 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]522 </ol>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]523
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]524 <p>The following extensions <b>are</b> known to be supported:</p>
525
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]526 <ol>
Chris Lattner7fe97dd2004-03-16 08:54:07 +0000[diff] [blame]527 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html#Labels%20as%20Values">Labels as Values</a>: Getting pointers to labels and computed gotos.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]528 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
529 <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>
Tanya Lattnerca26c3e2004-06-22 03:48:17 +0000[diff] [blame]530 <li><a href="http://gcc.gnu.org/onlinedocs/gcc-3.4.0/gcc/Lvalues.html#Lvalues">Lvalues</a>: Using <code>?:</code>, "<code>,</code>" and casts in lvalues.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]531 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
532 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
533 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
534 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
535 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
536 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
537 <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>
538 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
539 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Subscripting.html#Subscripting">Subscripting</a>: Any array can be subscripted, even if not an lvalue.</li>
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]540 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pointer-Arith.html#Pointer%20Arith">Pointer Arith</a>: Arithmetic on <code>void</code>-pointers and function pointers.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]541 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]542 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
543or arrays as values.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]544 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
Misha Brukmanc4b7bee2003-12-12 04:37:31 +0000[diff] [blame]545 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Cast-to-Union.html#Cast%20to%20Union">Cast to Union</a>: Casting to union type from any member of the union.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]546 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
547 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
548 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
549 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
550 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
551 <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>
552 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
553 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
554 <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>
555 <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>
556 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Names.html#Function%20Names">Function Names</a>: Printable strings which are the name of the current function.</li>
Chris Lattner25795bc2004-02-14 04:08:29 +0000[diff] [blame]557 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Return-Address.html#Return%20Address">Return Address</a>: Getting the return or frame address of a function.</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]558 <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>
559 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Attribute-Syntax.html#Attribute%20Syntax">Attribute Syntax</a>: Formal syntax for attributes.</li>
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]560 </ol></li>
561
562</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]563
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]564<p>If you run into GCC extensions which have not been included in any of these
565lists, please let us know (also including whether or not they work).</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]566
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]567</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]568
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]569<!-- ======================================================================= -->
570<div class="doc_subsection">
571 <a name="c++-fe">Known problems with the C++ front-end</a>
572</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]573
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]574<div class="doc_text">
575
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]576<p>For this release, the C++ front-end is considered to be fully functional but
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]577has not been tested as thoroughly as the C front-end. It has been tested and
578works for a number of non-trivial programs, but there may be lurking bugs.
579Please report any bugs or problems.</p>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]580
581</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]582
583<!-- _______________________________________________________________________ -->
Chris Lattner3a51be12004-02-14 04:12:41 +0000[diff] [blame]584<div class="doc_subsubsection">Bugs</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]585
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]586<div class="doc_text">
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]587
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]588<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]589<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]590 front-end</a>.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]591
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]592<li><b>IA-64 specific</b>: The C++ front-end does not use <a
593href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]594In particular, it just stores function pointers instead of function
595descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner04db8082004-08-02 20:29:51 +0000[diff] [blame]596LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner7962f712004-07-17 02:04:41 +0000[diff] [blame]597
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]598</ul>
599
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]600</div>
601
602<!-- _______________________________________________________________________ -->
603<div class="doc_subsubsection">
604 Notes
605</div>
606
607<div class="doc_text">
608
609<ul>
Chris Lattnere01fcfb2003-10-27 18:30:37 +0000[diff] [blame]610
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]611<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
612parser is significantly more standards compliant (and picky) than prior GCC
613versions. For more information, see the C++ section of the <a
Chris Lattner9e848092003-12-12 04:25:33 +0000[diff] [blame]614href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]615
616<li>Destructors for local objects are not always run when a <tt>longjmp</tt> is
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]617 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]618 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]619 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]620 better than most compilers).</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]621
Chris Lattner19092612003-10-02 16:38:05 +0000[diff] [blame]622<li>The LLVM C++ front-end follows the <a
623 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
624 This document, which is not Itanium specific, specifies a standard for name
625 mangling, class layout, v-table layout, RTTI formats, and other C++
626 representation issues. Because we use this API, code generated by the LLVM
627 compilers should be binary compatible with machine code generated by other
628 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
629 <i>However</i>, the exception handling mechanism used by LLVM is very
630 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]631 interact correctly</b>. </li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]632
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]633</ul>
Chris Lattnerfcc54b32003-10-07 22:14:37 +0000[diff] [blame]634
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]635</div>
636
637<!-- ======================================================================= -->
638<div class="doc_subsection">
639 <a name="x86-be">Known problems with the X86 back-end</a>
640</div>
641
642<div class="doc_text">
643
644<ul>
Chris Lattnerd5713882004-08-02 20:28:44 +0000[diff] [blame]645 <li>none yet</li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]646</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]647
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]648</div>
649
650<!-- ======================================================================= -->
651<div class="doc_subsection">
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]652 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]653</div>
654
655<div class="doc_text">
656
657<ul>
Misha Brukmanadb1c392004-07-12 16:55:41 +0000[diff] [blame]658<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
659several programs in the LLVM test suite</a></li>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]660</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]661
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]662</div>
663
664<!-- ======================================================================= -->
665<div class="doc_subsection">
Chris Lattnerf32a5f52004-11-07 01:55:32 +0000[diff] [blame]666 <a name="ppc-be">Known problems with the PowerPC back-end</a>
667</div>
668
669<div class="doc_text">
670
671<ul>
672<li>none yet</li>
673</ul>
674
675</div>
676
677<!-- ======================================================================= -->
678<div class="doc_subsection">
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]679 <a name="c-be">Known problems with the C back-end</a>
680</div>
681
682<div class="doc_text">
683
684<ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]685
686<li>The C back-end produces code that violates the ANSI C Type-Based Alias
687Analysis rules. As such, special options may be necessary to compile the code
688(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]689problem probably cannot be fixed.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]690
Chris Lattnere84843b2003-10-20 19:05:03 +0000[diff] [blame]691<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]692cannot include special floating point numbers like Not-A-Number or
693Infinity.</li>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]694
Chris Lattner2855ecd2003-11-04 20:06:53 +0000[diff] [blame]695<li><a href="http://llvm.cs.uiuc.edu/PR56">Zero arg vararg functions are not
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]696supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]697frontends.</li>
Chris Lattner2af46052003-10-24 04:03:19 +0000[diff] [blame]698
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]699</ul>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]700
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]701</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]702
703<!-- *********************************************************************** -->
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]704<div class="doc_section">
705 <a name="additionalinfo">Additional Information</a>
706</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]707<!-- *********************************************************************** -->
708
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]709<div class="doc_text">
710
711<p>A wide variety of additional information is available on the LLVM web page,
John Criswelld000e1d2003-12-18 16:43:17 +0000[diff] [blame]712including mailing lists and publications describing algorithms and components
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]713implemented in LLVM. The web page also contains versions of the API
714documentation which is up-to-date with the CVS version of the source code. You
715can access versions of these documents specific to this release by going into
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]716the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]717
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]718<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattner5eccca42003-12-12 21:22:16 +0000[diff] [blame]719us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
720lists</a>.</p>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]721
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]722</div>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]723
724<!-- *********************************************************************** -->
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]725
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]726<hr>
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]727<address>
Misha Brukman38847d52003-12-21 22:53:21 +0000[diff] [blame]728 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]729 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
730 <a href="http://validator.w3.org/check/referer"><img
731 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
732
Misha Brukmane0c891c2003-11-22 01:00:11 +0000[diff] [blame]733 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]734 Last modified: $Date$
Misha Brukman2061e892003-11-22 01:23:39 +0000[diff] [blame]735</address>
Chris Lattner79c3fe12003-10-02 04:57:28 +0000[diff] [blame]736
Misha Brukman500bc302003-11-22 00:38:41 +0000[diff] [blame]737</body>
738</html>