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1 38 julius
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.\" ========================================================================
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.\"
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.IX Title "GCJ 1"
132
.TH GCJ 1 "2007-10-07" "gcc-4.2.2" "GNU"
133
.SH "NAME"
134
gcj \- Ahead\-of\-time compiler for the Java language
135
.SH "SYNOPSIS"
136
.IX Header "SYNOPSIS"
137
gcj [\fB\-I\fR\fIdir\fR...] [\fB\-d\fR \fIdir\fR...]
138
    [\fB\-\-CLASSPATH\fR=\fIpath\fR] [\fB\-\-classpath\fR=\fIpath\fR]
139
    [\fB\-f\fR\fIoption\fR...] [\fB\-\-encoding\fR=\fIname\fR]
140
    [\fB\-\-main\fR=\fIclassname\fR] [\fB\-D\fR\fIname\fR[=\fIvalue\fR]...]
141
    [\fB\-C\fR] [\fB\-\-resource\fR \fIresource-name\fR] [\fB\-d\fR \fIdirectory\fR]
142
    [\fB\-W\fR\fIwarn\fR...]
143
    \fIsourcefile\fR...
144
.SH "DESCRIPTION"
145
.IX Header "DESCRIPTION"
146
As \fBgcj\fR is just another front end to \fBgcc\fR, it supports many
147
of the same options as gcc.    This manual only documents the
148
options specific to \fBgcj\fR.
149
.SH "OPTIONS"
150
.IX Header "OPTIONS"
151
.Sh "Input and output files"
152
.IX Subsection "Input and output files"
153
A \fBgcj\fR command is like a \fBgcc\fR command, in that it
154
consists of a number of options and file names.  The following kinds
155
of input file names are supported:
156
.IP "\fIfile\fR\fB.java\fR" 4
157
.IX Item "file.java"
158
Java source files.
159
.IP "\fIfile\fR\fB.class\fR" 4
160
.IX Item "file.class"
161
Java bytecode files.
162
.IP "\fIfile\fR\fB.zip\fR" 4
163
.IX Item "file.zip"
164
.PD 0
165
.IP "\fIfile\fR\fB.jar\fR" 4
166
.IX Item "file.jar"
167
.PD
168
An archive containing one or more \f(CW\*(C`.class\*(C'\fR files, all of
169
which are compiled.  The archive may be compressed.  Files in
170
an archive which don't end with \fB.class\fR are treated as
171
resource files; they are compiled into the resulting object file
172
as \fBcore:\fR URLs.
173
.IP "\fB@\fR\fIfile\fR" 4
174
.IX Item "@file"
175
A file containing a whitespace-separated list of input file names.
176
(Currently, these must all be \f(CW\*(C`.java\*(C'\fR source files, but that
177
may change.)
178
Each named file is compiled, just as if it had been on the command line.
179
.IP "\fIlibrary\fR\fB.a\fR" 4
180
.IX Item "library.a"
181
.PD 0
182
.IP "\fIlibrary\fR\fB.so\fR" 4
183
.IX Item "library.so"
184
.IP "\fB\-l\fR\fIlibname\fR" 4
185
.IX Item "-llibname"
186
.PD
187
Libraries to use when linking.  See the \fBgcc\fR manual.
188
.PP
189
You can specify more than one input file on the \fBgcj\fR command line,
190
in which case they will all be compiled.  If you specify a
191
\&\f(CW\*(C`\-o \f(CI\s-1FILENAME\s0\f(CW\*(C'\fR
192
option, all the input files will be compiled together, producing a
193
single output file, named \fI\s-1FILENAME\s0\fR.
194
This is allowed even when using \f(CW\*(C`\-S\*(C'\fR or \f(CW\*(C`\-c\*(C'\fR,
195
but not when using \f(CW\*(C`\-C\*(C'\fR or \f(CW\*(C`\-\-resource\*(C'\fR.
196
(This is an extension beyond the what plain \fBgcc\fR allows.)
197
(If more than one input file is specified, all must currently
198
be \f(CW\*(C`.java\*(C'\fR files, though we hope to fix this.)
199
.Sh "Input Options"
200
.IX Subsection "Input Options"
201
\&\fBgcj\fR has options to control where it looks to find files it needs.
202
For instance, \fBgcj\fR might need to load a class that is referenced
203
by the file it has been asked to compile.  Like other compilers for the
204
Java language, \fBgcj\fR has a notion of a \fIclass path\fR.  There are
205
several options and environment variables which can be used to
206
manipulate the class path.  When \fBgcj\fR looks for a given class, it
207
searches the class path looking for matching \fI.class\fR or
208
\&\fI.java\fR file.  \fBgcj\fR comes with a built-in class path which
209
points at the installed \fIlibgcj.jar\fR, a file which contains all the
210
standard classes.
211
.PP
212
In the below, a directory or path component can refer either to an
213
actual directory on the filesystem, or to a \fI.zip\fR or \fI.jar\fR
214
file, which \fBgcj\fR will search as if it is a directory.
215
.IP "\fB\-I\fR\fIdir\fR" 4
216
.IX Item "-Idir"
217
All directories specified by \f(CW\*(C`\-I\*(C'\fR are kept in order and prepended
218
to the class path constructed from all the other options.  Unless
219
compatibility with tools like \f(CW\*(C`javac\*(C'\fR is important, we recommend
220
always using \f(CW\*(C`\-I\*(C'\fR instead of the other options for manipulating the
221
class path.
222
.IP "\fB\-\-classpath=\fR\fIpath\fR" 4
223
.IX Item "--classpath=path"
224
This sets the class path to \fIpath\fR, a colon-separated list of paths
225
(on Windows-based systems, a semicolon-separate list of paths).
226
This does not override the builtin (\*(L"boot\*(R") search path.
227
.IP "\fB\-\-CLASSPATH=\fR\fIpath\fR" 4
228
.IX Item "--CLASSPATH=path"
229
Deprecated synonym for \f(CW\*(C`\-\-classpath\*(C'\fR.
230
.IP "\fB\-\-bootclasspath=\fR\fIpath\fR" 4
231
.IX Item "--bootclasspath=path"
232
Where to find the standard builtin classes, such as \f(CW\*(C`java.lang.String\*(C'\fR.
233
.IP "\fB\-\-extdirs=\fR\fIpath\fR" 4
234
.IX Item "--extdirs=path"
235
For each directory in the \fIpath\fR, place the contents of that
236
directory at the end of the class path.
237
.IP "\fB\s-1CLASSPATH\s0\fR" 4
238
.IX Item "CLASSPATH"
239
This is an environment variable which holds a list of paths.
240
.PP
241
The final class path is constructed like so:
242
.IP "\(bu" 4
243
First come all directories specified via \f(CW\*(C`\-I\*(C'\fR.
244
.IP "\(bu" 4
245
If \fB\-\-classpath\fR is specified, its value is appended.
246
Otherwise, if the \f(CW\*(C`CLASSPATH\*(C'\fR environment variable is specified,
247
then its value is appended.
248
Otherwise, the current directory (\f(CW"."\fR) is appended.
249
.IP "\(bu" 4
250
If \f(CW\*(C`\-\-bootclasspath\*(C'\fR was specified, append its value.
251
Otherwise, append the built-in system directory, \fIlibgcj.jar\fR.
252
.IP "\(bu" 4
253
Finally, if \f(CW\*(C`\-\-extdirs\*(C'\fR was specified, append the contents of the
254
specified directories at the end of the class path.  Otherwise, append
255
the contents of the built-in extdirs at \f(CW\*(C`$(prefix)/share/java/ext\*(C'\fR.
256
.PP
257
The classfile built by \fBgcj\fR for the class \f(CW\*(C`java.lang.Object\*(C'\fR
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(and placed in \f(CW\*(C`libgcj.jar\*(C'\fR) contains a special zero length
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attribute \f(CW\*(C`gnu.gcj.gcj\-compiled\*(C'\fR. The compiler looks for this
260
attribute when loading \f(CW\*(C`java.lang.Object\*(C'\fR and will report an error
261
if it isn't found, unless it compiles to bytecode (the option
262
\&\f(CW\*(C`\-fforce\-classes\-archive\-check\*(C'\fR can be used to override this
263
behavior in this particular case.)
264
.IP "\fB\-fforce\-classes\-archive\-check\fR" 4
265
.IX Item "-fforce-classes-archive-check"
266
This forces the compiler to always check for the special zero length
267
attribute \f(CW\*(C`gnu.gcj.gcj\-compiled\*(C'\fR in \f(CW\*(C`java.lang.Object\*(C'\fR and
268
issue an error if it isn't found.
269
.Sh "Encodings"
270
.IX Subsection "Encodings"
271
The Java programming language uses Unicode throughout.  In an effort to
272
integrate well with other locales, \fBgcj\fR allows \fI.java\fR files
273
to be written using almost any encoding.  \fBgcj\fR knows how to
274
convert these encodings into its internal encoding at compile time.
275
.PP
276
You can use the \f(CW\*(C`\-\-encoding=\f(CI\s-1NAME\s0\f(CW\*(C'\fR option to specify an
277
encoding (of a particular character set) to use for source files.  If
278
this is not specified, the default encoding comes from your current
279
locale.  If your host system has insufficient locale support, then
280
\&\fBgcj\fR assumes the default encoding to be the \fB\s-1UTF\-8\s0\fR encoding
281
of Unicode.
282
.PP
283
To implement \f(CW\*(C`\-\-encoding\*(C'\fR, \fBgcj\fR simply uses the host
284
platform's \f(CW\*(C`iconv\*(C'\fR conversion routine.  This means that in practice
285
\&\fBgcj\fR is limited by the capabilities of the host platform.
286
.PP
287
The names allowed for the argument \f(CW\*(C`\-\-encoding\*(C'\fR vary from platform
288
to platform (since they are not standardized anywhere).  However,
289
\&\fBgcj\fR implements the encoding named \fB\s-1UTF\-8\s0\fR internally, so if
290
you choose to use this for your source files you can be assured that it
291
will work on every host.
292
.Sh "Warnings"
293
.IX Subsection "Warnings"
294
\&\fBgcj\fR implements several warnings.  As with other generic
295
\&\fBgcc\fR warnings, if an option of the form \f(CW\*(C`\-Wfoo\*(C'\fR enables a
296
warning, then \f(CW\*(C`\-Wno\-foo\*(C'\fR will disable it.  Here we've chosen to
297
document the form of the warning which will have an effect \*(-- the
298
default being the opposite of what is listed.
299
.IP "\fB\-Wredundant\-modifiers\fR" 4
300
.IX Item "-Wredundant-modifiers"
301
With this flag, \fBgcj\fR will warn about redundant modifiers.  For
302
instance, it will warn if an interface method is declared \f(CW\*(C`public\*(C'\fR.
303
.IP "\fB\-Wextraneous\-semicolon\fR" 4
304
.IX Item "-Wextraneous-semicolon"
305
This causes \fBgcj\fR to warn about empty statements.  Empty statements
306
have been deprecated.
307
.IP "\fB\-Wno\-out\-of\-date\fR" 4
308
.IX Item "-Wno-out-of-date"
309
This option will cause \fBgcj\fR not to warn when a source file is
310
newer than its matching class file.  By default \fBgcj\fR will warn
311
about this.
312
.IP "\fB\-Wno\-deprecated\fR" 4
313
.IX Item "-Wno-deprecated"
314
Warn if a deprecated class, method, or field is referred to.
315
.IP "\fB\-Wunused\fR" 4
316
.IX Item "-Wunused"
317
This is the same as \fBgcc\fR's \f(CW\*(C`\-Wunused\*(C'\fR.
318
.IP "\fB\-Wall\fR" 4
319
.IX Item "-Wall"
320
This is the same as \f(CW\*(C`\-Wredundant\-modifiers \-Wextraneous\-semicolon
321
\&\-Wunused\*(C'\fR.
322
.Sh "Linking"
323
.IX Subsection "Linking"
324
To turn a Java application into an executable program,
325
you need to link it with the needed libraries, just as for C or \*(C+.
326
The linker by default looks for a global function named \f(CW\*(C`main\*(C'\fR.
327
Since Java does not have global functions, and a
328
collection of Java classes may have more than one class with a
329
\&\f(CW\*(C`main\*(C'\fR method, you need to let the linker know which of those
330
\&\f(CW\*(C`main\*(C'\fR methods it should invoke when starting the application.
331
You can do that in any of these ways:
332
.IP "\(bu" 4
333
Specify the class containing the desired \f(CW\*(C`main\*(C'\fR method
334
when you link the application, using the \f(CW\*(C`\-\-main\*(C'\fR flag,
335
described below.
336
.IP "\(bu" 4
337
Link the Java package(s) into a shared library (dll) rather than an
338
executable.  Then invoke the application using the \f(CW\*(C`gij\*(C'\fR program,
339
making sure that \f(CW\*(C`gij\*(C'\fR can find the libraries it needs.
340
.IP "\(bu" 4
341
Link the Java packages(s) with the flag \f(CW\*(C`\-lgij\*(C'\fR, which links
342
in the \f(CW\*(C`main\*(C'\fR routine from the \f(CW\*(C`gij\*(C'\fR command.
343
This allows you to select the class whose \f(CW\*(C`main\*(C'\fR method you
344
want to run when you run the application.  You can also use
345
other \f(CW\*(C`gij\*(C'\fR flags, such as \f(CW\*(C`\-D\*(C'\fR flags to set properties.
346
Using the \f(CW\*(C`\-lgij\*(C'\fR library (rather than the \f(CW\*(C`gij\*(C'\fR program
347
of the previous mechanism) has some advantages: it is compatible with
348
static linking, and does not require configuring or installing libraries.
349
.PP
350
These \f(CW\*(C`gij\*(C'\fR options relate to linking an executable:
351
.IP "\fB\-\-main=\fR\fI\s-1CLASSNAME\s0\fR" 4
352
.IX Item "--main=CLASSNAME"
353
This option is used when linking to specify the name of the class whose
354
\&\f(CW\*(C`main\*(C'\fR method should be invoked when the resulting executable is
355
run.
356
.IP "\fB\-D\fR\fIname\fR\fB[=\fR\fIvalue\fR\fB]\fR" 4
357
.IX Item "-Dname[=value]"
358
This option can only be used with \f(CW\*(C`\-\-main\*(C'\fR.  It defines a system
359
property named \fIname\fR with value \fIvalue\fR.  If \fIvalue\fR is not
360
specified then it defaults to the empty string.  These system properties
361
are initialized at the program's startup and can be retrieved at runtime
362
using the \f(CW\*(C`java.lang.System.getProperty\*(C'\fR method.
363
.IP "\fB\-lgij\fR" 4
364
.IX Item "-lgij"
365
Create an application whose command-line processing is that
366
of the \f(CW\*(C`gij\*(C'\fR command.
367
.Sp
368
This option is an alternative to using \f(CW\*(C`\-\-main\*(C'\fR; you cannot use both.
369
.IP "\fB\-static\-libgcj\fR" 4
370
.IX Item "-static-libgcj"
371
This option causes linking to be done against a static version of the
372
libgcj runtime library.  This option is only available if
373
corresponding linker support exists.
374
.Sp
375
\&\fBCaution:\fR Static linking of libgcj may cause essential parts
376
of libgcj to be omitted.  Some parts of libgcj use reflection to load
377
classes at runtime.  Since the linker does not see these references at
378
link time, it can omit the referred to classes.  The result is usually
379
(but not always) a \f(CW\*(C`ClassNotFoundException\*(C'\fR being thrown at
380
runtime. Caution must be used when using this option.  For more
381
details see:
382
<\fBhttp://gcc.gnu.org/wiki/Statically%20linking%20libgcj\fR>
383
.Sh "Code Generation"
384
.IX Subsection "Code Generation"
385
In addition to the many \fBgcc\fR options controlling code generation,
386
\&\fBgcj\fR has several options specific to itself.
387
.IP "\fB\-C\fR" 4
388
.IX Item "-C"
389
This option is used to tell \fBgcj\fR to generate bytecode
390
(\fI.class\fR files) rather than object code.
391
.IP "\fB\-\-resource\fR \fIresource-name\fR" 4
392
.IX Item "--resource resource-name"
393
This option is used to tell \fBgcj\fR to compile the contents of a
394
given file to object code so it may be accessed at runtime with the core
395
protocol handler as \fBcore:/\fR\fIresource-name\fR.  Note that
396
\&\fIresource-name\fR is the name of the resource as found at runtime; for
397
instance, it could be used in a call to \f(CW\*(C`ResourceBundle.getBundle\*(C'\fR.
398
The actual file name to be compiled this way must be specified
399
separately.
400
.IP "\fB\-d\fR \fIdirectory\fR" 4
401
.IX Item "-d directory"
402
When used with \f(CW\*(C`\-C\*(C'\fR, this causes all generated \fI.class\fR files
403
to be put in the appropriate subdirectory of \fIdirectory\fR.  By
404
default they will be put in subdirectories of the current working
405
directory.
406
.IP "\fB\-fno\-bounds\-check\fR" 4
407
.IX Item "-fno-bounds-check"
408
By default, \fBgcj\fR generates code which checks the bounds of all
409
array indexing operations.  With this option, these checks are omitted, which
410
can improve performance for code that uses arrays extensively.  Note that this
411
can result in unpredictable behavior if the code in question actually does
412
violate array bounds constraints.  It is safe to use this option if you are
413
sure that your code will never throw an \f(CW\*(C`ArrayIndexOutOfBoundsException\*(C'\fR.
414
.IP "\fB\-fno\-store\-check\fR" 4
415
.IX Item "-fno-store-check"
416
Don't generate array store checks.  When storing objects into arrays, a runtime
417
check is normally generated in order to ensure that the object is assignment
418
compatible with the component type of the array (which may not be known
419
at compile\-time).  With this option, these checks are omitted.  This can
420
improve performance for code which stores objects into arrays frequently.
421
It is safe to use this option if you are sure your code will never throw an
422
\&\f(CW\*(C`ArrayStoreException\*(C'\fR.
423
.IP "\fB\-fjni\fR" 4
424
.IX Item "-fjni"
425
With \fBgcj\fR there are two options for writing native methods: \s-1CNI\s0
426
and \s-1JNI\s0.  By default \fBgcj\fR assumes you are using \s-1CNI\s0.  If you are
427
compiling a class with native methods, and these methods are implemented
428
using \s-1JNI\s0, then you must use \f(CW\*(C`\-fjni\*(C'\fR.  This option causes
429
\&\fBgcj\fR to generate stubs which will invoke the underlying \s-1JNI\s0
430
methods.
431
.IP "\fB\-fno\-assert\fR" 4
432
.IX Item "-fno-assert"
433
Don't recognize the \f(CW\*(C`assert\*(C'\fR keyword.  This is for compatibility
434
with older versions of the language specification.
435
.IP "\fB\-fno\-optimize\-static\-class\-initialization\fR" 4
436
.IX Item "-fno-optimize-static-class-initialization"
437
When the optimization level is greater or equal to \f(CW\*(C`\-O2\*(C'\fR,
438
\&\fBgcj\fR will try to optimize the way calls into the runtime are made
439
to initialize static classes upon their first use (this optimization
440
isn't carried out if \f(CW\*(C`\-C\*(C'\fR was specified.) When compiling to native
441
code, \f(CW\*(C`\-fno\-optimize\-static\-class\-initialization\*(C'\fR will turn this
442
optimization off, regardless of the optimization level in use.
443
.IP "\fB\-\-disable\-assertions[=\fR\fIclass-or-package\fR\fB]\fR" 4
444
.IX Item "--disable-assertions[=class-or-package]"
445
Don't include code for checking assertions in the compiled code.
446
If \f(CW\*(C`=\f(CIclass-or-package\f(CW\*(C'\fR is missing disables assertion code
447
generation for all classes, unless overridden by a more
448
specific \f(CW\*(C`\-\-enable\-assertions\*(C'\fR flag.
449
If \fIclass-or-package\fR is a class name, only disables generating
450
assertion checks within the named class or its inner classes.
451
If \fIclass-or-package\fR is a package name, disables generating
452
assertion checks within the named package or a subpackage.
453
.Sp
454
By default, assertions are enabled when generating class files
455
or when not optimizing, and disabled when generating optimized binaries.
456
.IP "\fB\-\-enable\-assertions[=\fR\fIclass-or-package\fR\fB]\fR" 4
457
.IX Item "--enable-assertions[=class-or-package]"
458
Generates code to check assertions.  The option is perhaps misnamed,
459
as you still need to turn on assertion checking at run\-time,
460
and we don't support any easy way to do that.
461
So this flag isn't very useful yet, except to partially override
462
\&\f(CW\*(C`\-\-disable\-assertions\*(C'\fR.
463
.IP "\fB\-findirect\-dispatch\fR" 4
464
.IX Item "-findirect-dispatch"
465
\&\fBgcj\fR has a special binary compatibility \s-1ABI\s0, which is enabled
466
by the \f(CW\*(C`\-findirect\-dispatch\*(C'\fR option.  In this mode, the code
467
generated by \fBgcj\fR honors the binary compatibility guarantees
468
in the Java Language Specification, and the resulting object files do
469
not need to be directly linked against their dependencies.  Instead,
470
all dependencies are looked up at runtime.  This allows free mixing of
471
interpreted and compiled code.
472
.Sp
473
Note that, at present, \f(CW\*(C`\-findirect\-dispatch\*(C'\fR can only be used
474
when compiling \fI.class\fR files.  It will not work when compiling
475
from source.  \s-1CNI\s0 also does not yet work with the binary compatibility
476
\&\s-1ABI\s0.  These restrictions will be lifted in some future release.
477
.Sp
478
However, if you compile \s-1CNI\s0 code with the standard \s-1ABI\s0, you can call
479
it from code built with the binary compatibility \s-1ABI\s0.
480
.IP "\fB\-fbootstrap\-classes\fR" 4
481
.IX Item "-fbootstrap-classes"
482
This option can be use to tell \f(CW\*(C`libgcj\*(C'\fR that the compiled classes
483
should be loaded by the bootstrap loader, not the system class loader.
484
By default, if you compile a class and link it into an executable, it
485
will be treated as if it was loaded using the system class loader.
486
This is convenient, as it means that things like
487
\&\f(CW\*(C`Class.forName()\*(C'\fR will search \fB\s-1CLASSPATH\s0\fR to find the
488
desired class.
489
.IP "\fB\-freduced\-reflection\fR" 4
490
.IX Item "-freduced-reflection"
491
This option causes the code generated by \fBgcj\fR to contain a
492
reduced amount of the class meta-data used to support runtime
493
reflection. The cost of this savings is the loss of
494
the ability to use certain reflection capabilities of the standard
495
Java runtime environment. When set all meta-data except for that
496
which is needed to obtain correct runtime semantics is eliminated.
497
.Sp
498
For code that does not use reflection (i.e. the methods in the
499
\&\f(CW\*(C`java.lang.reflect\*(C'\fR package), \f(CW\*(C`\-freduced\-reflection\*(C'\fR
500
will result in proper operation with a savings in executable code size.
501
.Sp
502
\&\s-1JNI\s0 (\f(CW\*(C`\-fjni\*(C'\fR) and the binary compatibility \s-1ABI\s0
503
(\f(CW\*(C`\-findirect\-dispatch\*(C'\fR) do not work properly without full
504
reflection meta\-data.  Because of this, it is an error to use these options
505
with \f(CW\*(C`\-freduced\-reflection\*(C'\fR.
506
.Sp
507
\&\fBCaution:\fR If there is no reflection meta\-data, code that uses
508
a \f(CW\*(C`SecurityManager\*(C'\fR may not work properly.  Also calling
509
\&\f(CW\*(C`Class.forName()\*(C'\fR may fail if the calling method has no
510
reflection meta\-data.
511
.Sh "Configure-time Options"
512
.IX Subsection "Configure-time Options"
513
Some \fBgcj\fR code generations options affect the resulting \s-1ABI\s0, and
514
so can only be meaningfully given when \f(CW\*(C`libgcj\*(C'\fR, the runtime
515
package, is configured.  \f(CW\*(C`libgcj\*(C'\fR puts the appropriate options from
516
this group into a \fBspec\fR file which is read by \fBgcj\fR.  These
517
options are listed here for completeness; if you are using \f(CW\*(C`libgcj\*(C'\fR
518
then you won't want to touch these options.
519
.IP "\fB\-fuse\-boehm\-gc\fR" 4
520
.IX Item "-fuse-boehm-gc"
521
This enables the use of the Boehm \s-1GC\s0 bitmap marking code.  In particular
522
this causes \fBgcj\fR to put an object marking descriptor into each
523
vtable.
524
.IP "\fB\-fhash\-synchronization\fR" 4
525
.IX Item "-fhash-synchronization"
526
By default, synchronization data (the data used for \f(CW\*(C`synchronize\*(C'\fR,
527
\&\f(CW\*(C`wait\*(C'\fR, and \f(CW\*(C`notify\*(C'\fR) is pointed to by a word in each object.
528
With this option \fBgcj\fR assumes that this information is stored in a
529
hash table and not in the object itself.
530
.IP "\fB\-fuse\-divide\-subroutine\fR" 4
531
.IX Item "-fuse-divide-subroutine"
532
On some systems, a library routine is called to perform integer
533
division.  This is required to get exception handling correct when
534
dividing by zero.
535
.IP "\fB\-fcheck\-references\fR" 4
536
.IX Item "-fcheck-references"
537
On some systems it's necessary to insert inline checks whenever
538
accessing an object via a reference.  On other systems you won't need
539
this because null pointer accesses are caught automatically by the
540
processor.
541
.SH "SEE ALSO"
542
.IX Header "SEE ALSO"
543
\&\fIgcc\fR\|(1), \fIgcjh\fR\|(1), \fIgjnih\fR\|(1), \fIgij\fR\|(1), \fIjv\-scan\fR\|(1), \fIjcf\-dump\fR\|(1), \fIgfdl\fR\|(7),
544
and the Info entries for \fIgcj\fR and \fIgcc\fR.
545
.SH "COPYRIGHT"
546
.IX Header "COPYRIGHT"
547
Copyright (c) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
548
.PP
549
Permission is granted to copy, distribute and/or modify this document
550
under the terms of the \s-1GNU\s0 Free Documentation License, Version 1.2 or
551
any later version published by the Free Software Foundation; with the
552
Invariant Sections being \*(L"\s-1GNU\s0 General Public License\*(R", the Front-Cover
553
texts being (a) (see below), and with the Back-Cover Texts being (b)
554
(see below).  A copy of the license is included in the
555
man page \fIgfdl\fR\|(7).
556
.PP
557
(a) The \s-1FSF\s0's Front-Cover Text is:
558
.PP
559
.Vb 1
560
\&     A GNU Manual
561
.Ve
562
.PP
563
(b) The \s-1FSF\s0's Back-Cover Text is:
564
.PP
565
.Vb 3
566
\&     You have freedom to copy and modify this GNU Manual, like GNU
567
\&     software.  Copies published by the Free Software Foundation raise
568
\&     funds for GNU development.
569
.Ve

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