Gitiles
Code Review Sign In
gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / ba9485222c6caa188cd7fe73ce8668b0aee904ac / . / docs / ReleaseNotes.html
blob: 085fc7536b7f9219c93e9674b267c5f745728ace [file] [log] [blame]
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]1<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
2 "http://www.w3.org/TR/html4/strict.dtd">
3<html>
4<head>
5 <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
6 <link rel="stylesheet" href="llvm.css" type="text/css">
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]7 <title>LLVM 2.3 Release Notes</title>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]8</head>
9<body>
10
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]11<div class="doc_title">LLVM 2.3 Release Notes</div>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]12
13<ol>
14 <li><a href="#intro">Introduction</a></li>
15 <li><a href="#whatsnew">What's New?</a></li>
16 <li><a href="GettingStarted.html">Installation Instructions</a></li>
17 <li><a href="#portability">Portability and Supported Platforms</a></li>
18 <li><a href="#knownproblems">Known Problems</a>
19 <li><a href="#additionalinfo">Additional Information</a></li>
20</ol>
21
22<div class="doc_author">
23 <p>Written by the <a href="http://llvm.org">LLVM Team</a><p>
24</div>
25
26<!-- *********************************************************************** -->
27<div class="doc_section">
28 <a name="intro">Introduction</a>
29</div>
30<!-- *********************************************************************** -->
31
32<div class="doc_text">
33
34<p>This document contains the release notes for the LLVM compiler
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]35infrastructure, release 2.3. Here we describe the status of LLVM, including
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]36major improvements from the previous release and any known problems. All LLVM
37releases may be downloaded from the <a href="http://llvm.org/releases/">LLVM
38releases web site</a>.</p>
39
40<p>For more information about LLVM, including information about the latest
41release, please check out the <a href="http://llvm.org/">main LLVM
42web site</a>. If you have questions or comments, the <a
43href="http://mail.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVM developer's mailing
44list</a> is a good place to send them.</p>
45
46<p>Note that if you are reading this file from a Subversion checkout or the
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]47main LLVM web page, this document applies to the <i>next</i> release, not the
48current one. To see the release notes for a specific releases, please see the
49<a href="http://llvm.org/releases/">releases page</a>.</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]50
51</div>
52
53<!-- *********************************************************************** -->
54<div class="doc_section">
55 <a name="whatsnew">What's New?</a>
56</div>
57<!-- *********************************************************************** -->
58
59<div class="doc_text">
60
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]61<p>This is the fourteenth public release of the LLVM Compiler Infrastructure.
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]62It includes a large number of features and refinements from LLVM 2.2.</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]63
64</div>
65
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]66<!-- Unfinished features in 2.3:
Chris Lattner8fda4952008-02-10 07:46:44 +0000[diff] [blame]67 Index Set Splitting not enabled by default
68 Machine LICM
69 Machine Sinking
70 LegalizeDAGTypes
71 -->
72
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]73<!--=========================================================================-->
74<div class="doc_subsection">
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]75<a name="deprecation">Removed features in LLVM 2.3</a>
Chris Lattner41bf8e92008-02-10 07:04:35 +0000[diff] [blame]76</div>
77
78<div class="doc_text">
79
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]80<p>LLVM 2.2 was the last LLVM release to support llvm-gcc 4.0 and llvm-upgrade.
81llvm-gcc 4.0 has been replaced with llvm-gcc 4.2. llvm-upgrade was useful for
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]82upgrading LLVM 1.9 files to LLVM 2.x syntax, but you can always use a previous
83LLVM release to do this. One nice impact of this is that the LLVM regressionn
84test suite no longer depends on llvm-upgrade, which makes it run faster.</p>
Chris Lattnere0798082008-02-06 18:00:06 +0000[diff] [blame]85
86</div>
87
88<!--=========================================================================-->
89<div class="doc_subsection">
90<a name="majorfeatures">Major New Features</a>
91</div>
92
93<div class="doc_text">
94
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]95<p>LLVM 2.3 includes several major new capabilities:</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]96
97<ul>
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]98<li>Multiple Return Value Support</li>
Chris Lattnerba948522008-06-05 06:57:39 +0000[diff] [blame^]99
100
101<li><p>LLVM 2.3 includes a complete reimplementation of the "llvmc" tool. It is
102designed to overcome several problems of the original llvmc and to provide a
103superset of the features as the 'gcc' driver.</p>
104
105<p>The main features of llvmc2 is:</p>
106
107<ul>
108<li>Extended handling of command line options and smart rules for
109dispatching them to different tools.</li>
110<li>Flexible (and extensible) rules for defining different tools.</li>
111<li>The different intermediate steps performed by tools are represented
112as edged in the abstract graph.</li>
113</l>The 'language' for driver behaviour definition is tablegen and thus
114it's relatively easy to add new features.</li>
115<li>The definition of driver is transformed into set of C++ classes, thus
116no runtime interpretation is needed.</li>
117</ul>
118
119</li>
120
121
122
123
Chris Lattner5ba16862008-02-10 08:18:42 +0000[diff] [blame]124</ul>
125
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]126</div>
127
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]128
129<!--=========================================================================-->
130<div class="doc_subsection">
131<a name="frontends">llvm-gcc 4.2 Improvements and Clang</a>
132</div>
133
134<div class="doc_text">
135
136<p>LLVM 2.3 fully supports llvm-gcc 4.2 front-end.</p>
137
138<p>llvm-gcc 4.2 includes numerous fixes to better support the Objective-C
139front-end. Objective-C now works very well on Mac OS/X.</p>
140
141<p>llvm-gcc 4.2 includes many other fixes which improve conformance with the
142relevant parts of the GCC testsuite.</p>
143
144<p>The <a href="http://clang.llvm.org/">clang project</a> is an effort to build
145a set of new 'llvm native' front-end technologies for the LLVM optimizer
146and code generator. Currently, its C and Objective-C support is maturing
147nicely, and it has advanced source-to-source analysis and transformation
148capabilities. If you are interested in building source-level tools for C and
149Objective-C (and eventually C++), you should take a look. However, note that
150clang is not an official part of the LLVM 2.3 release. If you are interested in
151this project, please see its <a href="http://clang.llvm.org/">web site</a>.</p>
152
153</div>
154
155
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]156<!--=========================================================================-->
157<div class="doc_subsection">
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]158<a name="coreimprovements">LLVM Core Improvements</a>
159</div>
160
161<div class="doc_text">
162<p>New features include:
163</p>
164
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]165
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]166Common linkage?
167
168Atomic operation support, Alpha, X86, PowerPC. "__sync_syncronize"
169
170<ul>
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]171</ul>
172
173</div>
174
175<!--=========================================================================-->
176<div class="doc_subsection">
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]177<a name="codegen">Code Generator Improvements</a>
178</div>
179
180<div class="doc_text">
181
Chris Lattner8fda4952008-02-10 07:46:44 +0000[diff] [blame]182<p>We put a significant amount of work into the code generator infrastructure,
183which allows us to implement more aggressive algorithms and make it run
184faster:</p>
Chris Lattner7d2b1102007-09-26 05:44:21 +0000[diff] [blame]185
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]186<ul>
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]187<li>MemOperand in the code generator: describe me!.</li>
188<li>i128 support and APInt through most of codegen.</li>
Chris Lattner8fda4952008-02-10 07:46:44 +0000[diff] [blame]189</ul>
190
191</div>
192
193<!--=========================================================================-->
194<div class="doc_subsection">
195<a name="optimizer">Optimizer Improvements</a>
196</div>
197
198<div class="doc_text">
199
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]200<p>In addition to a huge array of bug fixes and minor performance tweaks, the
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]201LLVM 2.3 optimizers support a few major enhancements:</p>
Chris Lattner8fda4952008-02-10 07:46:44 +0000[diff] [blame]202
203<ul>
204
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]205<li>Loop index set splitting on by default: describe me.</li>
206<li>LLVM includes a new memcpy optimization pass which optimizes out dead
207memcpy calls and unneeded copies of aggregates.</li>
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]208</ul>
209
210</div>
211
212
213<!--=========================================================================-->
214<div class="doc_subsection">
215<a name="targetspecific">Target Specific Improvements</a>
216</div>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]217
218<div class="doc_text">
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]219<p>New target-specific features include:
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]220</p>
221
222<ul>
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]223<li>llvm-gcc's X86-64 ABI conformance is far improved, particularly in the
224 area of passing and returning structures by value. llvm-gcc Compiled code
225 now interoperates very well on X86-64 systems with other compilers.</li>
226
227<li>The LLVM X86 backend now supports the support SSE 4.1 instruction set, and
228 the llvm-gcc 4.2 front-end supports the SSE 4.1 compiler builtins.</li>
229
230<li>The X86 backend now does a number of optimizations that aim to avoid
231 converting numbers back and forth from SSE registers to the X87 floating
232 point stack.</li>
Chris Lattnerba948522008-06-05 06:57:39 +0000[diff] [blame^]233
234<li>The X86 backend supports stack realignment, which is particularly useful for
235 vector code on OS's without 16-byte aligned stacks.</li>
Chris Lattnerc5a4e312008-06-05 06:25:56 +0000[diff] [blame]236
237<li>The X86 backend now supports the "sseregparm" options in GCC, which allow
238 functions to be tagged as passing floating point values in SSE
239 registers.</li>
240
241<li>Trampolines (taking the address of a nested function) now work on
242 Linux/x86-64.</li>
243
244
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]245</ul>
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]246
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]247</div>
248
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]249<!--=========================================================================-->
250<div class="doc_subsection">
251<a name="otherimprovements">Other Improvements</a>
252</div>
253
254<div class="doc_text">
255<p>New features include:
256</p>
257
258<ul>
Chris Lattnerba948522008-06-05 06:57:39 +0000[diff] [blame^]259<li>LLVM now builds with GCC 4.3.</li>
Chris Lattnerb0d6c502007-09-21 03:54:09 +0000[diff] [blame]260</ul>
261
262</div>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]263
264<!-- *********************************************************************** -->
265<div class="doc_section">
266 <a name="portability">Portability and Supported Platforms</a>
267</div>
268<!-- *********************************************************************** -->
269
270<div class="doc_text">
271
272<p>LLVM is known to work on the following platforms:</p>
273
274<ul>
275<li>Intel and AMD machines running Red Hat Linux, Fedora Core and FreeBSD
276 (and probably other unix-like systems).</li>
Chris Lattnerbd633de92008-02-06 06:30:34 +0000[diff] [blame]277<li>PowerPC and X86-based Mac OS X systems, running 10.3 and above in 32-bit and
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]278 64-bit modes.</li>
Chris Lattnere0798082008-02-06 18:00:06 +0000[diff] [blame]279<li>Intel and AMD machines running on Win32 using MinGW libraries (native).</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]280<li>Intel and AMD machines running on Win32 with the Cygwin libraries (limited
281 support is available for native builds with Visual C++).</li>
282<li>Sun UltraSPARC workstations running Solaris 8.</li>
283<li>Alpha-based machines running Debian GNU/Linux.</li>
284<li>Itanium-based machines running Linux and HP-UX.</li>
285</ul>
286
Chris Lattnerba948522008-06-05 06:57:39 +0000[diff] [blame^]287<p>The core LLVM infrastructure uses GNU autoconf to adapt itself
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]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>
291
292</div>
293
294<!-- *********************************************************************** -->
295<div class="doc_section">
296 <a name="knownproblems">Known Problems</a>
297</div>
298<!-- *********************************************************************** -->
299
300<div class="doc_text">
301
302<p>This section contains all known problems with the LLVM system, listed by
303component. As new problems are discovered, they will be added to these
304sections. If you run into a problem, please check the <a
305href="http://llvm.org/bugs/">LLVM bug database</a> and submit a bug if
306there isn't already one.</p>
307
308</div>
309
310<!-- ======================================================================= -->
311<div class="doc_subsection">
312 <a name="experimental">Experimental features included with this release</a>
313</div>
314
315<div class="doc_text">
316
317<p>The following components of this LLVM release are either untested, known to
318be broken or unreliable, or are in early development. These components should
319not be relied on, and bugs should not be filed against them, but they may be
320useful to some people. In particular, if you would like to work on one of these
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]321components, please contact us on the <a
322href="http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev">LLVMdev list</a>.</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]323
324<ul>
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]325<li>The MSIL, IA64, Alpha, SPU, and MIPS backends are experimental.</li>
Chris Lattnerbd633de92008-02-06 06:30:34 +0000[diff] [blame]326<li>The LLC "<tt>-filetype=asm</tt>" (the default) is the only supported
327 value for this option.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]328</ul>
329
330</div>
331
332<!-- ======================================================================= -->
333<div class="doc_subsection">
334 <a name="x86-be">Known problems with the X86 back-end</a>
335</div>
336
337<div class="doc_text">
338
339<ul>
340<li>The X86 backend does not yet support <a href="http://llvm.org/PR879">inline
341 assembly that uses the X86 floating point stack</a>.</li>
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]342<li>The X86 backend generates inefficient floating point code when configured to
343 generate code for systems that don't have SSE2.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]344</ul>
345
346</div>
347
348<!-- ======================================================================= -->
349<div class="doc_subsection">
350 <a name="ppc-be">Known problems with the PowerPC back-end</a>
351</div>
352
353<div class="doc_text">
354
355<ul>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]356<li>The Linux PPC32/ABI support needs testing for the interpreter and static
357compilation, and lacks support for debug information.</li>
358</ul>
359
360</div>
361
362<!-- ======================================================================= -->
363<div class="doc_subsection">
364 <a name="arm-be">Known problems with the ARM back-end</a>
365</div>
366
367<div class="doc_text">
368
369<ul>
370<li>Thumb mode works only on ARMv6 or higher processors. On sub-ARMv6
Duncan Sands1827fa62007-09-26 15:59:54 +0000[diff] [blame]371processors, thumb programs can crash or produce wrong
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]372results (<a href="http://llvm.org/PR1388">PR1388</a>).</li>
373<li>Compilation for ARM Linux OABI (old ABI) is supported, but not fully tested.
374</li>
Chris Lattnerc3649452008-02-10 08:17:19 +0000[diff] [blame]375<li>There is a bug in QEMU-ARM (&lt;= 0.9.0) which causes it to incorrectly execute
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]376programs compiled with LLVM. Please use more recent versions of QEMU.</li>
377</ul>
378
379</div>
380
381<!-- ======================================================================= -->
382<div class="doc_subsection">
383 <a name="sparc-be">Known problems with the SPARC back-end</a>
384</div>
385
386<div class="doc_text">
387
388<ul>
389<li>The SPARC backend only supports the 32-bit SPARC ABI (-m32), it does not
390 support the 64-bit SPARC ABI (-m64).</li>
391</ul>
392
393</div>
394
395<!-- ======================================================================= -->
396<div class="doc_subsection">
397 <a name="alpha-be">Known problems with the Alpha back-end</a>
398</div>
399
400<div class="doc_text">
401
402<ul>
403
404<li>On 21164s, some rare FP arithmetic sequences which may trap do not have the
405appropriate nops inserted to ensure restartability.</li>
406
407</ul>
408</div>
409
410<!-- ======================================================================= -->
411<div class="doc_subsection">
412 <a name="ia64-be">Known problems with the IA64 back-end</a>
413</div>
414
415<div class="doc_text">
416
417<ul>
418
419<li>C++ programs are likely to fail on IA64, as calls to <tt>setjmp</tt> are
420made where the argument is not 16-byte aligned, as required on IA64. (Strictly
421speaking this is not a bug in the IA64 back-end; it will also be encountered
422when building C++ programs using the C back-end.)</li>
423
424<li>The C++ front-end does not use <a href="http://llvm.org/PR406">IA64
425ABI compliant layout of v-tables</a>. In particular, it just stores function
426pointers instead of function descriptors in the vtable. This bug prevents
427mixing C++ code compiled with LLVM with C++ objects compiled by other C++
428compilers.</li>
429
430<li>There are a few ABI violations which will lead to problems when mixing LLVM
431output with code built with other compilers, particularly for floating-point
432programs.</li>
433
434<li>Defining vararg functions is not supported (but calling them is ok).</li>
435
436<li>The Itanium backend has bitrotted somewhat.</li>
437</ul>
438
439</div>
440
441<!-- ======================================================================= -->
442<div class="doc_subsection">
443 <a name="c-be">Known problems with the C back-end</a>
444</div>
445
446<div class="doc_text">
447
448<ul>
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]449<li><a href="http://llvm.org/PR802">The C backend has only basic support for
450 inline assembly code</a>.</li>
Chris Lattnere0194462007-09-26 06:01:35 +0000[diff] [blame]451<li><a href="http://llvm.org/PR1658">The C backend violates the ABI of common
452 C++ programs</a>, preventing intermixing between C++ compiled by the CBE and
453 C++ code compiled with LLC or native compilers.</li>
Duncan Sandsbd0ad6e2008-02-10 13:40:55 +0000[diff] [blame]454<li>The C backend does not support all exception handling constructs.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]455</ul>
456
457</div>
458
459
460<!-- ======================================================================= -->
461<div class="doc_subsection">
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]462 <a name="c-fe">Known problems with the llvm-gcc C front-end</a>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]463</div>
464
465<!-- _______________________________________________________________________ -->
466<div class="doc_subsubsection">Bugs</div>
467
468<div class="doc_text">
469
Chris Lattnere0798082008-02-06 18:00:06 +0000[diff] [blame]470<p>llvm-gcc does not currently support <a href="http://llvm.org/PR869">Link-Time
471Optimization</a> on most platforms "out-of-the-box". Please inquire on the
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]472llvmdev mailing list if you are interested.</p>
473
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]474<p>The only major language feature of GCC not supported by llvm-gcc is
475 the <tt>__builtin_apply</tt> family of builtins. However, some extensions
476 are only supported on some targets. For example, trampolines are only
477 supported on some targets, which are used when you take the address of a
478 nested function.</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]479
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]480<p>If you run into GCC extensions which are not supported, please let us know.
481</p>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]482
483</div>
484
485<!-- ======================================================================= -->
486<div class="doc_subsection">
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]487 <a name="c++-fe">Known problems with the llvm-gcc C++ front-end</a>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]488</div>
489
490<div class="doc_text">
491
492<p>The C++ front-end is considered to be fully
493tested and works for a number of non-trivial programs, including LLVM
494itself, Qt, Mozilla, etc.</p>
495
496<ul>
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]497<li>Exception handling works well on the X86 and PowerPC targets, including
498x86-64 darwin. This works when linking to a libstdc++ compiled by GCC. It is
499supported on x86-64 linux, but that is disabled by default in this release.</li>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]500</ul>
501
502</div>
503
504
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]505<!-- ======================================================================= -->
506<div class="doc_subsection">
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]507 <a name="ada-fe">Known problems with the llvm-gcc Ada front-end</a>
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]508</div>
509
510<div class="doc_text">
511The llvm-gcc 4.2 Ada compiler works fairly well, however this is not a mature
512technology and problems should be expected.
513<ul>
514<li>The Ada front-end currently only builds on x86-32. This is mainly due
515to lack of trampoline support (pointers to nested functions) on other platforms,
516however it <a href="http://llvm.org/PR2006">also fails to build on x86-64</a>
517which does support trampolines.</li>
518<li>The Ada front-end <a href="http://llvm.org/PR2007">fails to bootstrap</a>.
519Workaround: configure with --disable-bootstrap.</li>
520<li>The c380004 and <a href="http://llvm.org/PR2010">c393010</a> ACATS tests
521fail (c380004 also fails with gcc-4.2 mainline).</li>
522<li>Many gcc specific Ada tests continue to crash the compiler.</li>
523<li>The -E binder option (exception backtraces)
524<a href="http://llvm.org/PR1982">does not work</a> and will result in programs
525crashing if an exception is raised. Workaround: do not use -E.</li>
526<li>Only discrete types <a href="http://llvm.org/PR1981">are allowed to start
527or finish at a non-byte offset</a> in a record. Workaround: do not pack records
528or use representation clauses that result in a field of a non-discrete type
529starting or finishing in the middle of a byte.</li>
530<li>The lli interpreter <a href="http://llvm.org/PR2009">considers 'main'
531as generated by the Ada binder to be invalid</a>.
532Workaround: hand edit the file to use pointers for argv and envp rather than
533integers.</li>
534<li>The -fstack-check option <a href="http://llvm.org/PR2008">is ignored</a>.</li>
535</ul>
536</div>
537
538<!-- ======================================================================= -->
539<div class="doc_subsection">
Chris Lattner499c07c2008-06-05 06:35:40 +0000[diff] [blame]540 <a name="fortran-fe">Known problems with the llvm-gcc Fortran front-end</a>
Chris Lattnerdaeb3232008-02-12 06:29:45 +0000[diff] [blame]541</div>
542
543<div class="doc_text">
544
545<ul>
546<li>The llvm-gcc 4.2 gfortran front-end supports a broad range of Fortran code, but does
547<a href="http://llvm.org/PR1971">not support EQUIVALENCE yet</a>.</li>
548</ul>
549</div>
550
551
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]552
553<!-- *********************************************************************** -->
554<div class="doc_section">
555 <a name="additionalinfo">Additional Information</a>
556</div>
557<!-- *********************************************************************** -->
558
559<div class="doc_text">
560
561<p>A wide variety of additional information is available on the <a
562href="http://llvm.org">LLVM web page</a>, in particular in the <a
563href="http://llvm.org/docs/">documentation</a> section. The web page also
564contains versions of the API documentation which is up-to-date with the
565Subversion version of the source code.
566You can access versions of these documents specific to this release by going
567into the "<tt>llvm/doc/</tt>" directory in the LLVM tree.</p>
568
569<p>If you have any questions or comments about LLVM, please feel free to contact
570us via the <a href="http://llvm.org/docs/#maillist"> mailing
571lists</a>.</p>
572
573</div>
574
575<!-- *********************************************************************** -->
576
577<hr>
578<address>
579 <a href="http://jigsaw.w3.org/css-validator/check/referer"><img
580 src="http://jigsaw.w3.org/css-validator/images/vcss" alt="Valid CSS!"></a>
581 <a href="http://validator.w3.org/check/referer"><img
Chris Lattner5ba16862008-02-10 08:18:42 +0000[diff] [blame]582 src="http://www.w3.org/Icons/valid-html401" alt="Valid HTML 4.01!"></a>
Dan Gohmanf17a25c2007-07-18 16:29:46 +0000[diff] [blame]583
584 <a href="http://llvm.org/">LLVM Compiler Infrastructure</a><br>
585 Last modified: $Date$
586</address>
587
588</body>
589</html>