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gerrit-public.fairphone.software / toolchain / llvm-project / 9d63271caa5b697bb4bd19c028f329c0dbf04c5f / . / llvm / docs / ReleaseNotes.html
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4<head>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]7 <title>LLVM 1.4 Release Notes</title>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]8</head>
9<body>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]10
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]11<div class="doc_title">LLVM 1.4 Release Notes</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]12
13<ol>
Misha Brukman80731b92003-11-22 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 Lattner77a51732004-04-30 22:17:12 +0000[diff] [blame]16 <li><a href="GettingStarted.html">Installation Instructions</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]17 <li><a href="#portability">Portability and Supported Platforms</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]18 <li><a href="#knownproblems">Known Problems</a>
19 <ul>
Chris Lattner1a7e43c2004-04-01 00:41:31 +0000[diff] [blame]20 <li><a href="#experimental">Experimental features included in this
21 release</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>
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]26 <li><a href="#sparcv9-be">Known problems with the SparcV9 Back-end</a>
Chris Lattnerdf925ce2004-11-07 01:55:32 +0000[diff] [blame]27 <li><a href="#ppc-be">Known problems with the PowerPC Back-end</a>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]28 <li><a href="#c-be">Known problems with the C back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]29 </ul></li>
30 <li><a href="#additionalinfo">Additional Information</a></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]31</ol>
32
Chris Lattner020e1fc2004-05-23 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]35</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]36
37<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]38<div class="doc_section">
39 <a name="intro">Introduction</a>
40</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]41<!-- *********************************************************************** -->
42
Misha Brukman80731b92003-11-22 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 Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]46infrastructure, release 1.4. Here we describe the status of LLVM, including any
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]47known problems and bug fixes from the previous release. The most up-to-date
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]48version of this document can be found on the <a
Chris Lattner163c3262004-08-16 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 Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]50not reading this on the LLVM web pages, you should probably go there because
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]51this document may be updated after the release.</p>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]52
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]53<p>For more information about LLVM, including information about potentially more
Chris Lattnere7525b52003-10-07 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]57list</a> is a good place to send them.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]58
Chris Lattnere76e9ab2003-12-12 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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]62href="http://llvm.cs.uiuc.edu/releases/">releases page</a>.</p>
63
64</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]65
66<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]67<div class="doc_section">
68 <a name="whatsnew">What's New?</a>
69</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]70<!-- *********************************************************************** -->
71
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]72<div class="doc_text">
73
Chris Lattner163c3262004-08-16 00:20:18 +0000[diff] [blame]74<p>This is the fifth public release of the LLVM compiler infrastructure.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]75
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]76<p> At this time, LLVM is known to correctly compile and run all C &amp; C++
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]77SPEC CPU95 &amp; 2000 benchmarks, the Olden benchmarks, and the Ptrdist
Chris Lattner55266332004-10-16 18:35:57 +0000[diff] [blame]78benchmarks, and <b>many</b> other C and C++ programs.</p>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]79
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]80</div>
81
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]82<!--=========================================================================-->
83<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]84<a name="newfeatures">This release implements the following new features:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]85</div>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]86
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]87<div class="doc_text">
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]88<ol>
Chris Lattnere0267142004-11-27 19:24:06 +0000[diff] [blame]89 <li>LLVM now includes a JIT for the PowerPC target.</li>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]90 <li>LLVM now optimizes global variables significantly more than it did
91 before.
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]92 </li>
Reid Spencer493d9c22004-11-25 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 Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]135 </li>
Chris Lattnerd5f52882004-11-17 18:19:32 +0000[diff] [blame]136 <li>The LLVM source code is much more compatible with Microsoft Visual C++,
Reid Spencer493d9c22004-11-25 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 Lattnerb7696902004-11-22 22:09:58 +0000[diff] [blame]140 <li>The target-to-JIT interfaces <a href="http://llvm.cs.uiuc.edu/PR283">are
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]141 now much simpler</a> and more powerful.
142 </li>
Chris Lattnere0267142004-11-27 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 Lattner592db402003-11-19 22:05:38 +0000[diff] [blame]145</ol>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]146
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]147</div>
148
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]149
150<!--=========================================================================-->
151<div class="doc_subsubsection">
152In this release, the following missing features were implemented:
153</div>
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]154
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]155<div class="doc_text">
156
Chris Lattner4491de62003-11-08 04:28:55 +0000[diff] [blame]157<ol>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]158 <li><a href="http://llvm.cs.uiuc.edu/PR419">JIT interface should support
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]159 arbitrary calls</a>
160 </li>
Reid Spencere4190fa2004-11-18 18:38:58 +0000[diff] [blame]161 <li>The <tt>llvm-ar</tt> tool was previously incomplete and didn't properly
162 support other ar(1) implementations. This has been corrected. <tt>llvm-ar</tt>
163 now fully supports all archive editing functions, table of contents listing,
164 extraction, and printing. It can also read BSD4.4/MacOSX and SVR4 style
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]165 archives. See <a href="CommandGuide/html/llvm-ar.html">llvm-ar</a> for
166 details.
167 </li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]168</ol>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]169
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]170</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]171
172<!--=========================================================================-->
173<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]174<a name="qualityofimp">In this release, the following Quality of Implementation
175issues were fixed:</a>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]176</div>
177
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]178<div class="doc_text">
179
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]180<ol>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]181 <li><a href="http://llvm.cs.uiuc.edu/PR426">[llvmg++] Tons of warnings
182 are spewed when linking to libstdc++</a>
183 </li>
184 <li><a href="http://llvm.cs.uiuc.edu/PR352">include/{Support,Config} ->
185 include/llvm/{Support,Config}</a>
186 </li>
Reid Spencerb4e3ec82004-11-22 18:40:51 +0000[diff] [blame]187 <li>The names of the libraries generated by compiling LLVM source have been
188 changed to ensure they do not conflict with other packages upon installation.
189 Each LLVM library is now prefixed with LLVM and uses mixed clase. For example,
190 the library <tt>libasmparser.a</tt> in 1.3 has become
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]191 <tt>libLLVMAsmParser.a</tt> in release 1.4.
192 </li>
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]193</ol>
194
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]195</div>
196
Chris Lattner4df78f02003-12-20 03:42:11 +0000[diff] [blame]197<!--=========================================================================-->
198<div class="doc_subsubsection">
Chris Lattner8ebf2532004-02-25 16:36:51 +0000[diff] [blame]199In this release, the following build problems were fixed:
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]200</div>
201
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]202<div class="doc_text">
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]203<ol>
Reid Spencer26864642004-11-25 06:07:42 +0000[diff] [blame]204 <li><a href="http://llvm.cs.uiuc.edu/PR256">[autoconf] further standardizing
205 autoconf usage</a>. Various improvements in the configure.ac script were
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]206 made as well as the makefile system.
207 </li>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]208</ol>
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]209</div>
Brian Gaeke8b05e4f2004-01-16 21:55:04 +0000[diff] [blame]210
211<!--=========================================================================-->
212<div class="doc_subsubsection">
Chris Lattner2ad48782004-05-02 04:19:15 +0000[diff] [blame]213<a name="codequality">This release includes the following Code Quality
214improvements:</a>
Chris Lattner23257062004-05-23 20:42:08 +0000[diff] [blame]215</div>
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]216
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]217<div class="doc_text">
Chris Lattner639579c2003-10-27 17:06:39 +0000[diff] [blame]218<ol>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]219 <li><a href="http://llvm.cs.uiuc.edu/PR362">Ugly code generated for
220 std::min/std::max</a>
221 </li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]222</ol>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]223</div>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]224
225<!--=========================================================================-->
226<div class="doc_subsubsection">
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]227<a name="bugfix">In this release, the following bugs in the previous release
228were fixed:</a>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]229</div>
230
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]231<div class="doc_text">
232
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]233<p>Bugs fixed in the LLVM Core:</p>
Chris Lattnere7525b52003-10-07 21:38:31 +0000[diff] [blame]234
235<ol>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]236 <li><a href="http://llvm.cs.uiuc.edu/PR420">[licm] LICM invalidates alias
237 analysis info and uses broken information</a> (optimizer crash)</li>
238 <li><a href="http://llvm.cs.uiuc.edu/PR422">[asmwriter] Asmwriter is really
239 slow for functions with lots of values</a></li>
240 <li><a href="http://llvm.cs.uiuc.edu/PR423">[anders-aa] Andersen's AA is
241 completely broken in LLVM 1.3</a></li>
242 <li><a href="http://llvm.cs.uiuc.edu/PR430">[bcwriter] Empty compaction
243 tables defined</a></li>
244 <li><a href="http://llvm.cs.uiuc.edu/PR227">[X86] llc output for functions
245 w/certain names tickles GNU 'as' bugs</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]246</ol>
247
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]248<p>Bugs in the C/C++ front-end:</p>
249
250<ol>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]251 <li><a href="http://llvm.cs.uiuc.edu/PR445">[llvmg++] not enough templates are
252 instantiated</a></li>
253 <li><a href="http://llvm.cs.uiuc.edu/PR450">[llvmg++] Extern const globals
254 cannot be marked 'constant' if they have nontrivial ctors or dtors</a></li>
255 <li><a href="http://llvm.cs.uiuc.edu/PR461">[llvmgcc] Crash compiling unnamed
Chris Lattner6345ee292004-11-25 06:31:42 +0000[diff] [blame]256 bitfield which does not increase struct size</a></li>
Chris Lattnerba7bd472003-12-06 20:22:41 +0000[diff] [blame]257</ol>
Brian Gaeke730d8d62004-08-24 07:43:48 +0000[diff] [blame]258
259<p>Bugs fixed in the Sparc V9 back-end:</p>
260
261<ol>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]262 <li><a href="http://llvm.cs.uiuc.edu/PR428">[sparcv9] regalloc assertion
Brian Gaeke730d8d62004-08-24 07:43:48 +0000[diff] [blame]263 failure with certain indirect calls</a></li>
264</ol>
265
Chris Lattner21a90402004-05-24 04:50:25 +0000[diff] [blame]266</div>
Reid Spencer3e58f582004-05-23 17:23:13 +0000[diff] [blame]267
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]268<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]269<div class="doc_section">
270 <a name="portability">Portability and Supported Platforms</a>
271</div>
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]272<!-- *********************************************************************** -->
273
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]274<div class="doc_text">
275
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]276<p>LLVM is known to work in the following platforms:</p>
277
278<ul>
279<li>Intel and AMD machines running Red Hat Linux and FreeBSD (and probably
280 other unix-like systems).</li>
281<li>Sun UltraSPARC workstations running Solaris 8.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]282<li>Intel and AMD machines running on Win32 with the Cygwin libraries.</li>
Chris Lattnerd0af8e22004-11-25 06:33:10 +0000[diff] [blame]283<li>PowerPC-based Mac OS X boxes, running 10.2 and above.</li>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]284</ul>
285
Brian Gaekee3e557e2004-05-09 05:28:35 +0000[diff] [blame]286<p>The core LLVM infrastructure uses
287<a href="http://www.gnu.org/software/autoconf/">GNU autoconf</a> to adapt itself
288to the machine and operating system on which it is built. However, minor
289porting may be required to get LLVM to work on new platforms. We welcome your
290portability patches and reports of successful builds or error messages.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]291
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]292<p>Note that the LLVM build system does not currently support directories with
293spaces on them when running on Win32/cygwin. We strongly recommend running
294LLVM and the C frontend out of a top-level directory without spaces (e.g.,
Chris Lattnerce1a3842004-06-01 19:41:30 +0000[diff] [blame]295<tt>/cygdrive/c/llvm</tt>). Also, make sure to install <b>all</b> of the
296cygwin packages. By default, many important tools are not installed that
Chris Lattnera752fce2004-08-16 20:20:46 +0000[diff] [blame]297are needed by the LLVM build process or test suite (e.g., /bin/time). Finally,
298please make sure that there are no directories with spaces in them in your
299PATH environment variable.</p>
Chris Lattner2c7b0872004-06-01 18:22:41 +0000[diff] [blame]300
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]301</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]302
303<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]304<div class="doc_section">
305 <a name="knownproblems">Known Problems</a>
306</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]307<!-- *********************************************************************** -->
308
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]309<div class="doc_text">
310
311<p>This section contains all known problems with the LLVM system, listed by
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]312component. As new problems are discovered, they will be added to these
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]313sections. If you run into a problem, please check the <a
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]314href="http://llvm.cs.uiuc.edu/bugs/">LLVM bug database</a> and submit a bug if
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]315there isn't already one.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]316
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]317</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]318
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]319<!-- ======================================================================= -->
320<div class="doc_subsection">
321 <a name="experimental">Experimental features included with this release</a>
322</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]323
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]324<div class="doc_text">
325
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]326<p>The following components of this LLVM release are either untested, known to
327be broken or unreliable, or are in early development. These components should
328not be relied on, and bugs should not be filed against them, but they may be
329useful to some people. In particular, if you would like to work on one of these
330components, please contact us on the llvmdev list.</p>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]331
332<ul>
333<li>The following passes are incomplete or buggy: <tt>-pgmdep, -memdep,
Chris Lattner09f3ac92004-09-14 16:43:13 +0000[diff] [blame]334 -ipmodref, -cee, -branch-combine, -instloops, -paths</tt></li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]335<li>The <tt>-pre</tt> pass is incomplete (there are cases it doesn't handle that
336 it should) and not thoroughly tested.</li>
Chris Lattnerb911de42004-03-14 02:03:02 +0000[diff] [blame]337<li>The <tt>llvm-db</tt> tool is in a very early stage of development.</li>
338</ul>
339
340</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]341
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]342<!-- ======================================================================= -->
343<div class="doc_subsection">
344 <a name="core">Known problems with the LLVM Core</a>
345</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]346
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]347<div class="doc_text">
348
349<ul>
Reid Spencer493d9c22004-11-25 22:38:30 +0000[diff] [blame]350 <li>In the JIT, <tt>dlsym</tt> on a symbol compiled by the JIT will not work.
351 </li>
352 <li>The JIT does not use mutexes to protect its internal data structures. As
353 such, execution of a threaded program could cause these data structures to be
354 corrupted.
355 </li>
356 <li>Linking in static archive files (.a files) is slow by default because
357 there is no symbol table in the archive. To remedy this, run
358 <a href="CommandGuide/html/llvm-ranlib.html"><tt>llvm-ranlib</tt></a> on the
359 archive to add an LLVM symbol table.
360 </li>
361 <li>The gccld program <a href="http://llvm.cs.uiuc.edu/PR139">does not link
362 objects/archives in the order specified on the command line.</a>
363 </li>
364 <li><a href="http://llvm.cs.uiuc.edu/PR240">The lower-invoke pass does not
365 mark values live across a setjmp as volatile</a>. This missing feature
366 only affects targets whose setjmp/longjmp libraries do not save and restore
367 the entire register file.</li>
Reid Spencer6caee972004-11-25 22:43:58 +0000[diff] [blame]368 <li><a href="http://llvm.cs.uiuc.edu/PR427">[bytecode] Assertion on V1
369 Bytecode Files</a>. This bug won't be fixed because V1 bytecode had its own
370 problems, no one is using V1 bytecode any more, and the fix is non-trivial.
371 </li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]372</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]373</div>
374
375<!-- ======================================================================= -->
376<div class="doc_subsection">
377 <a name="c-fe">Known problems with the C front-end</a>
378</div>
Chris Lattner178f3db2003-10-02 05:07:23 +0000[diff] [blame]379
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]380<!-- _______________________________________________________________________ -->
Chris Lattner5a8a7282003-12-14 05:03:43 +0000[diff] [blame]381<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]382
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]383<div class="doc_text">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]384<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]385<li>C99 Variable sized arrays do not release stack memory when they go out of
386 scope. Thus, the following program may run out of stack space:
387<pre>
388 for (i = 0; i != 1000000; ++i) {
389 int X[n];
390 foo(X);
391 }
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]392</pre></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]393
Misha Brukmanfa50a222004-05-12 21:46:05 +0000[diff] [blame]394<li>Initialization of global union variables can only be done <a
395href="http://llvm.cs.uiuc.edu/bugs/show_bug.cgi?id=162">with the largest union
396member</a>.</li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]397
Misha Brukman017f2f32004-04-19 02:56:49 +0000[diff] [blame]398<li><a href="http://llvm.cs.uiuc.edu/PR244">[llvm-gcc] Error when an implicitly
399external function is re-declared as static</a></li>
Chris Lattner1ab58dd2004-03-16 21:39:04 +0000[diff] [blame]400
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]401</ul>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]402</div>
403
404<!-- _______________________________________________________________________ -->
405<div class="doc_subsubsection">
406 Notes
407</div>
408
409<div class="doc_text">
410
411<ul>
412
413<li>Inline assembly is not yet supported.</li>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]414
415<li>"long double" is transformed by the front-end into "double". There is no
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]416support for floating point data types of any size other than 32 and 64
417bits.</li>
418
419<li>The following Unix system functionality has not been tested and may not
420work:
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]421 <ol>
422 <li><tt>sigsetjmp</tt>, <tt>siglongjmp</tt> - These are not turned into the
423 appropriate <tt>invoke</tt>/<tt>unwind</tt> instructions. Note that
424 <tt>setjmp</tt> and <tt>longjmp</tt> <em>are</em> compiled correctly.
425 <li><tt>getcontext</tt>, <tt>setcontext</tt>, <tt>makecontext</tt>
426 - These functions have not been tested.
427 </ol></li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]428
429<li>Although many GCC extensions are supported, some are not. In particular,
430 the following extensions are known to <b>not be</b> supported:
431 <ol>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]432 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Local-Labels.html#Local%20Labels">Local Labels</a>: Labels local to a block.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]433 <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>
434 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constructing-Calls.html#Constructing%20Calls">Constructing Calls</a>: Dispatching a call to another function.</li>
435 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html#Extended%20Asm">Extended Asm</a>: Assembler instructions with C expressions as operands.</li>
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]436 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Constraints.html#Constraints">Constraints</a>: Constraints for asm operands.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]437 <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>
438 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Explicit-Reg-Vars.html#Explicit%20Reg%20Vars">Explicit Reg Vars</a>: Defining variables residing in specified registers.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]439 <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>
440 <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>
441 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Thread-Local.html#Thread-Local">Thread-Local</a>: Per-thread variables.</li>
442 <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]443 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]444
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]445 <p>The following GCC extensions are <b>partially</b> supported. An ignored
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]446 attribute means that the LLVM compiler ignores the presence of the attribute,
447 but the code should still work. An unsupported attribute is one which is
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]448 ignored by the LLVM compiler and will cause a different interpretation of
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]449 the program.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]450
451 <ol>
452 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html#Variable%20Length">Variable Length</a>:
453 Arrays whose length is computed at run time.<br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]454 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]455
456 <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]457
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]458 Declaring that functions have no side effects or that they can never
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]459 return.<br>
460
461 <b>Supported:</b> <tt>format</tt>, <tt>format_arg</tt>, <tt>non_null</tt>,
462 <tt>constructor</tt>, <tt>destructor</tt>, <tt>unused</tt>,
463 <tt>deprecated</tt>, <tt>warn_unused_result</tt>, <tt>weak</tt><br>
464
465 <b>Ignored:</b> <tt>noreturn</tt>, <tt>noinline</tt>,
466 <tt>always_inline</tt>, <tt>pure</tt>, <tt>const</tt>, <tt>nothrow</tt>,
467 <tt>malloc</tt>, <tt>no_instrument_function</tt>, <tt>cdecl</tt><br>
468
469 <b>Unsupported:</b> <tt>used</tt>, <tt>section</tt>, <tt>alias</tt>,
470 <tt>visibility</tt>, <tt>regparm</tt>, <tt>stdcall</tt>,
471 <tt>fastcall</tt>, all other target specific attributes</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]472
473 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Variable-Attributes.html#Variable%20Attributes">Variable Attributes</a>:
474 Specifying attributes of variables.<br>
475 <b>Supported:</b> <tt>cleanup</tt>, <tt>common</tt>, <tt>nocommon</tt>,
476 <tt>deprecated</tt>, <tt>transparent_union</tt>,
477 <tt>unused</tt>, <tt>weak</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]478
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]479 <b>Unsupported:</b> <tt>aligned</tt>, <tt>mode</tt>, <tt>packed</tt>,
480 <tt>section</tt>, <tt>shared</tt>, <tt>tls_model</tt>,
481 <tt>vector_size</tt>, <tt>dllimport</tt>,
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]482 <tt>dllexport</tt>, all target specific attributes.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]483
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]484 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Type-Attributes.html#Type%20Attributes">Type Attributes</a>: Specifying attributes of types.<br>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]485 <b>Supported:</b> <tt>transparent_union</tt>, <tt>unused</tt>,
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]486 <tt>deprecated</tt>, <tt>may_alias</tt><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]487
488 <b>Unsupported:</b> <tt>aligned</tt>, <tt>packed</tt>,
489 all target specific attributes.</li>
490
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]491 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#Other%20Builtins">Other Builtins</a>:
492 Other built-in functions.<br>
493 We support all builtins which have a C language equivalent (e.g.,
494 <tt>__builtin_cos</tt>), <tt>__builtin_alloca</tt>,
495 <tt>__builtin_types_compatible_p</tt>, <tt>__builtin_choose_expr</tt>,
Chris Lattnerb7c4bac2004-06-18 06:26:29 +0000[diff] [blame]496 <tt>__builtin_constant_p</tt>, and <tt>__builtin_expect</tt>
497 (currently ignored). We also support builtins for ISO C99 floating
498 point comparison macros (e.g., <tt>__builtin_islessequal</tt>).</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]499 </ol>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]500
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]501 <p>The following extensions <b>are</b> known to be supported:</p>
502
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]503 <ol>
Chris Lattnerd3dc8502004-03-16 08:54:07 +0000[diff] [blame]504 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Labels-as-Values.html#Labels%20as%20Values">Labels as Values</a>: Getting pointers to labels and computed gotos.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]505 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Statement-Exprs.html#Statement%20Exprs">Statement Exprs</a>: Putting statements and declarations inside expressions.</li>
506 <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 Lattnerce33a1b2004-06-22 03:48:17 +0000[diff] [blame]507 <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 Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]508 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Conditionals.html#Conditionals">Conditionals</a>: Omitting the middle operand of a <code>?:</code> expression.</li>
509 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Long-Long.html#Long%20Long">Long Long</a>: Double-word integers.</li>
510 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Complex.html#Complex">Complex</a>: Data types for complex numbers.</li>
511 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Hex-Floats.html#Hex%20Floats">Hex Floats</a>:Hexadecimal floating-point constants.</li>
512 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html#Zero%20Length">Zero Length</a>: Zero-length arrays.</li>
513 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Empty-Structures.html#Empty%20Structures">Empty Structures</a>: Structures with no members.</li>
514 <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>
515 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Escaped-Newlines.html#Escaped%20Newlines">Escaped Newlines</a>: Slightly looser rules for escaped newlines.</li>
516 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Subscripting.html#Subscripting">Subscripting</a>: Any array can be subscripted, even if not an lvalue.</li>
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]517 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Pointer-Arith.html#Pointer%20Arith">Pointer Arith</a>: Arithmetic on <code>void</code>-pointers and function pointers.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]518 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Initializers.html#Initializers">Initializers</a>: Non-constant initializers.</li>
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]519 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Compound-Literals.html#Compound%20Literals">Compound Literals</a>: Compound literals give structures, unions,
520or arrays as values.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]521 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html#Designated%20Inits">Designated Inits</a>: Labeling elements of initializers.</li>
Misha Brukman8395d732003-12-12 04:37:31 +0000[diff] [blame]522 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Cast-to-Union.html#Cast%20to%20Union">Cast to Union</a>: Casting to union type from any member of the union.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]523 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Case-Ranges.html#Case%20Ranges">Case Ranges</a>: `case 1 ... 9' and such.</li>
524 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Mixed-Declarations.html#Mixed%20Declarations">Mixed Declarations</a>: Mixing declarations and code.</li>
525 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Prototypes.html#Function%20Prototypes">Function Prototypes</a>: Prototype declarations and old-style definitions.</li>
526 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/C---Comments.html#C++%20Comments">C++ Comments</a>: C++ comments are recognized.</li>
527 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Dollar-Signs.html#Dollar%20Signs">Dollar Signs</a>: Dollar sign is allowed in identifiers.</li>
528 <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>
529 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Alignment.html#Alignment">Alignment</a>: Inquiring about the alignment of a type or variable.</li>
530 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Inline.html#Inline">Inline</a>: Defining inline functions (as fast as macros).</li>
531 <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>
532 <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>
533 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Function-Names.html#Function%20Names">Function Names</a>: Printable strings which are the name of the current function.</li>
Chris Lattner3646dad2004-02-14 04:08:29 +0000[diff] [blame]534 <li><a href="http://gcc.gnu.org/onlinedocs/gcc/Return-Address.html#Return%20Address">Return Address</a>: Getting the return or frame address of a function.</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]535 <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>
536 <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]537 </ol></li>
538
539</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]540
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]541<p>If you run into GCC extensions which have not been included in any of these
542lists, please let us know (also including whether or not they work).</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]543
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]544</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]545
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]546<!-- ======================================================================= -->
547<div class="doc_subsection">
548 <a name="c++-fe">Known problems with the C++ front-end</a>
549</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]550
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]551<div class="doc_text">
552
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]553<p>For this release, the C++ front-end is considered to be fully functional but
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]554has not been tested as thoroughly as the C front-end. It has been tested and
555works for a number of non-trivial programs, but there may be lurking bugs.
556Please report any bugs or problems.</p>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]557
558</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]559
560<!-- _______________________________________________________________________ -->
Chris Lattner141ebb62004-02-14 04:12:41 +0000[diff] [blame]561<div class="doc_subsubsection">Bugs</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]562
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]563<div class="doc_text">
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<li>The C++ front-end inherits all problems afflicting the <a href="#c-fe">C
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]567 front-end</a>.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]568
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]569<li><b>IA-64 specific</b>: The C++ front-end does not use <a
570href="http://llvm.cs.uiuc.edu/PR406">IA64 ABI compliant layout of v-tables</a>.
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]571In particular, it just stores function pointers instead of function
572descriptors in the vtable. This bug prevents mixing C++ code compiled with
Chris Lattner2fd93492004-08-02 20:29:51 +0000[diff] [blame]573LLVM with C++ objects compiled by other C++ compilers.</li>
Chris Lattner041e6c92004-07-17 02:04:41 +0000[diff] [blame]574
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]575</ul>
576
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]577</div>
578
579<!-- _______________________________________________________________________ -->
580<div class="doc_subsubsection">
581 Notes
582</div>
583
584<div class="doc_text">
585
586<ul>
Chris Lattnerd2a74272003-10-27 18:30:37 +0000[diff] [blame]587
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]588<li>The C++ front-end is based on a pre-release of the GCC 3.4 C++ parser. This
589parser is significantly more standards compliant (and picky) than prior GCC
590versions. For more information, see the C++ section of the <a
Chris Lattnere76e9ab2003-12-12 04:25:33 +0000[diff] [blame]591href="http://gcc.gnu.org/gcc-3.4/changes.html">GCC 3.4 release notes</a>.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]592
593<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]594 performed. In particular, destructors for objects in the <tt>longjmp</tt>ing
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]595 function and in the <tt>setjmp</tt> receiver function may not be run.
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]596 Objects in intervening stack frames will be destroyed, however (which is
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]597 better than most compilers).</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]598
Chris Lattner62495762003-10-02 16:38:05 +0000[diff] [blame]599<li>The LLVM C++ front-end follows the <a
600 href="http://www.codesourcery.com/cxx-abi">Itanium C++ ABI</a>.
601 This document, which is not Itanium specific, specifies a standard for name
602 mangling, class layout, v-table layout, RTTI formats, and other C++
603 representation issues. Because we use this API, code generated by the LLVM
604 compilers should be binary compatible with machine code generated by other
605 Itanium ABI C++ compilers (such as G++, the Intel and HP compilers, etc).
606 <i>However</i>, the exception handling mechanism used by LLVM is very
607 different from the model used in the Itanium ABI, so <b>exceptions will not
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]608 interact correctly</b>. </li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]609
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]610</ul>
Chris Lattner46ecf612003-10-07 22:14:37 +0000[diff] [blame]611
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]612</div>
613
614<!-- ======================================================================= -->
615<div class="doc_subsection">
616 <a name="x86-be">Known problems with the X86 back-end</a>
617</div>
618
619<div class="doc_text">
620
621<ul>
Chris Lattner5cd40922004-08-02 20:28:44 +0000[diff] [blame]622 <li>none yet</li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]623</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]624
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]625</div>
626
627<!-- ======================================================================= -->
628<div class="doc_subsection">
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]629 <a name="sparcv9-be">Known problems with the SparcV9 back-end</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]630</div>
631
632<div class="doc_text">
633
634<ul>
Misha Brukmana516e992004-07-12 16:55:41 +0000[diff] [blame]635<li><a href="http://llvm.cs.uiuc.edu/PR60">[sparcv9] SparcV9 backend miscompiles
636several programs in the LLVM test suite</a></li>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]637</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]638
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]639</div>
640
641<!-- ======================================================================= -->
642<div class="doc_subsection">
Chris Lattnerdf925ce2004-11-07 01:55:32 +0000[diff] [blame]643 <a name="ppc-be">Known problems with the PowerPC back-end</a>
644</div>
645
646<div class="doc_text">
647
648<ul>
649<li>none yet</li>
650</ul>
651
652</div>
653
654<!-- ======================================================================= -->
655<div class="doc_subsection">
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]656 <a name="c-be">Known problems with the C back-end</a>
657</div>
658
659<div class="doc_text">
660
661<ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]662
663<li>The C back-end produces code that violates the ANSI C Type-Based Alias
664Analysis rules. As such, special options may be necessary to compile the code
665(for example, GCC requires the <tt>-fno-strict-aliasing</tt> option). This
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]666problem probably cannot be fixed.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]667
Chris Lattnera623e482003-10-20 19:05:03 +0000[diff] [blame]668<li><a href="http://llvm.cs.uiuc.edu/PR33">Initializers for global variables</a>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]669cannot include special floating point numbers like Not-A-Number or
670Infinity.</li>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]671
Chris Lattnerc679fbb2003-11-04 20:06:53 +0000[diff] [blame]672<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]673supported</a>. This should not affect LLVM produced by the C or C++
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]674frontends.</li>
Chris Lattnerb28c3282003-10-24 04:03:19 +0000[diff] [blame]675
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]676</ul>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]677
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]678</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]679
680<!-- *********************************************************************** -->
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]681<div class="doc_section">
682 <a name="additionalinfo">Additional Information</a>
683</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]684<!-- *********************************************************************** -->
685
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]686<div class="doc_text">
687
688<p>A wide variety of additional information is available on the LLVM web page,
John Criswell86a3a482003-12-18 16:43:17 +0000[diff] [blame]689including mailing lists and publications describing algorithms and components
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]690implemented in LLVM. The web page also contains versions of the API
691documentation which is up-to-date with the CVS version of the source code. You
692can access versions of these documents specific to this release by going into
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]693the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]694
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]695<p>If you have any questions or comments about LLVM, please feel free to contact
Chris Lattnerb84f3322003-12-12 21:22:16 +0000[diff] [blame]696us via the <a href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">mailing
697lists</a>.</p>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]698
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]699</div>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]700
701<!-- *********************************************************************** -->
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]702
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]703<hr>
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]704<address>
Misha Brukman8834af92003-12-21 22:53:21 +0000[diff] [blame]705 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]706 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
707 <a href="http://validator.w3.org/check/referer"><img
708 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!" /></a>
709
Misha Brukman7cb4e382003-11-22 01:00:11 +0000[diff] [blame]710 <a href="http://llvm.cs.uiuc.edu">The LLVM Compiler Infrastructure</a><br>
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]711 Last modified: $Date$
Misha Brukman68aab3b2003-11-22 01:23:39 +0000[diff] [blame]712</address>
Chris Lattner3d482502003-10-02 04:57:28 +0000[diff] [blame]713
Misha Brukman80731b92003-11-22 00:38:41 +0000[diff] [blame]714</body>
715</html>