X-Git-Url: https://oss.titaniummirror.com/gitweb/?a=blobdiff_plain;f=gcc%2Fdoc%2Fgcj.1;fp=gcc%2Fdoc%2Fgcj.1;h=84fee486af5b9e61699208d682fa614d2d8676cf;hb=6fed43773c9b0ce596dca5686f37ac3fc0fa11c0;hp=0000000000000000000000000000000000000000;hpb=27b11d56b743098deb193d510b337ba22dc52e5c;p=msp430-gcc.git diff --git a/gcc/doc/gcj.1 b/gcc/doc/gcj.1 new file mode 100644 index 00000000..84fee486 --- /dev/null +++ b/gcc/doc/gcj.1 @@ -0,0 +1,586 @@ +.\" Automatically generated by Pod::Man 2.16 (Pod::Simple 3.07) +.\" +.\" Standard preamble: +.\" ======================================================================== +.de Sh \" Subsection heading +.br +.if t .Sp +.ne 5 +.PP +\fB\\$1\fR +.PP +.. +.de Sp \" Vertical space (when we can't use .PP) +.if t .sp .5v +.if n .sp +.. +.de Vb \" Begin verbatim text +.ft CW +.nf +.ne \\$1 +.. +.de Ve \" End verbatim text +.ft R +.fi +.. +.\" Set up some character translations and predefined strings. \*(-- will +.\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left +.\" double quote, and \*(R" will give a right double quote. \*(C+ will +.\" give a nicer C++. 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Always turn off hyphenation; it makes +.\" way too many mistakes in technical documents. +.if n .ad l +.nh +.SH "NAME" +gcj \- Ahead\-of\-time compiler for the Java language +.SH "SYNOPSIS" +.IX Header "SYNOPSIS" +gcj [\fB\-I\fR\fIdir\fR...] [\fB\-d\fR \fIdir\fR...] + [\fB\-\-CLASSPATH\fR=\fIpath\fR] [\fB\-\-classpath\fR=\fIpath\fR] + [\fB\-f\fR\fIoption\fR...] [\fB\-\-encoding\fR=\fIname\fR] + [\fB\-\-main\fR=\fIclassname\fR] [\fB\-D\fR\fIname\fR[=\fIvalue\fR]...] + [\fB\-C\fR] [\fB\-\-resource\fR \fIresource-name\fR] [\fB\-d\fR \fIdirectory\fR] + [\fB\-W\fR\fIwarn\fR...] + \fIsourcefile\fR... +.SH "DESCRIPTION" +.IX Header "DESCRIPTION" +As \fBgcj\fR is just another front end to \fBgcc\fR, it supports many +of the same options as gcc. This manual only documents the +options specific to \fBgcj\fR. +.SH "OPTIONS" +.IX Header "OPTIONS" +.Sh "Input and output files" +.IX Subsection "Input and output files" +A \fBgcj\fR command is like a \fBgcc\fR command, in that it +consists of a number of options and file names. The following kinds +of input file names are supported: +.IP "\fIfile\fR\fB.java\fR" 4 +.IX Item "file.java" +Java source files. +.IP "\fIfile\fR\fB.class\fR" 4 +.IX Item "file.class" +Java bytecode files. +.IP "\fIfile\fR\fB.zip\fR" 4 +.IX Item "file.zip" +.PD 0 +.IP "\fIfile\fR\fB.jar\fR" 4 +.IX Item "file.jar" +.PD +An archive containing one or more \f(CW\*(C`.class\*(C'\fR files, all of +which are compiled. The archive may be compressed. Files in +an archive which don't end with \fB.class\fR are treated as +resource files; they are compiled into the resulting object file +as \fBcore:\fR URLs. +.IP "\fB@\fR\fIfile\fR" 4 +.IX Item "@file" +A file containing a whitespace-separated list of input file names. +(Currently, these must all be \f(CW\*(C`.java\*(C'\fR source files, but that +may change.) +Each named file is compiled, just as if it had been on the command line. +.IP "\fIlibrary\fR\fB.a\fR" 4 +.IX Item "library.a" +.PD 0 +.IP "\fIlibrary\fR\fB.so\fR" 4 +.IX Item "library.so" +.IP "\fB\-l\fR\fIlibname\fR" 4 +.IX Item "-llibname" +.PD +Libraries to use when linking. See the \fBgcc\fR manual. +.PP +You can specify more than one input file on the \fBgcj\fR command line, +in which case they will all be compiled. If you specify a +\&\f(CW\*(C`\-o \f(CIFILENAME\f(CW\*(C'\fR +option, all the input files will be compiled together, producing a +single output file, named \fI\s-1FILENAME\s0\fR. +This is allowed even when using \f(CW\*(C`\-S\*(C'\fR or \f(CW\*(C`\-c\*(C'\fR, +but not when using \f(CW\*(C`\-C\*(C'\fR or \f(CW\*(C`\-\-resource\*(C'\fR. +(This is an extension beyond the what plain \fBgcc\fR allows.) +(If more than one input file is specified, all must currently +be \f(CW\*(C`.java\*(C'\fR files, though we hope to fix this.) +.Sh "Input Options" +.IX Subsection "Input Options" +\&\fBgcj\fR has options to control where it looks to find files it needs. +For instance, \fBgcj\fR might need to load a class that is referenced +by the file it has been asked to compile. Like other compilers for the +Java language, \fBgcj\fR has a notion of a \fIclass path\fR. There are +several options and environment variables which can be used to +manipulate the class path. When \fBgcj\fR looks for a given class, it +searches the class path looking for matching \fI.class\fR or +\&\fI.java\fR file. \fBgcj\fR comes with a built-in class path which +points at the installed \fIlibgcj.jar\fR, a file which contains all the +standard classes. +.PP +In the text below, a directory or path component can refer either to an +actual directory on the filesystem, or to a \fI.zip\fR or \fI.jar\fR +file, which \fBgcj\fR will search as if it is a directory. +.IP "\fB\-I\fR\fIdir\fR" 4 +.IX Item "-Idir" +All directories specified by \f(CW\*(C`\-I\*(C'\fR are kept in order and prepended +to the class path constructed from all the other options. Unless +compatibility with tools like \f(CW\*(C`javac\*(C'\fR is important, we recommend +always using \f(CW\*(C`\-I\*(C'\fR instead of the other options for manipulating the +class path. +.IP "\fB\-\-classpath=\fR\fIpath\fR" 4 +.IX Item "--classpath=path" +This sets the class path to \fIpath\fR, a colon-separated list of paths +(on Windows-based systems, a semicolon-separate list of paths). +This does not override the builtin (\*(L"boot\*(R") search path. +.IP "\fB\-\-CLASSPATH=\fR\fIpath\fR" 4 +.IX Item "--CLASSPATH=path" +Deprecated synonym for \f(CW\*(C`\-\-classpath\*(C'\fR. +.IP "\fB\-\-bootclasspath=\fR\fIpath\fR" 4 +.IX Item "--bootclasspath=path" +Where to find the standard builtin classes, such as \f(CW\*(C`java.lang.String\*(C'\fR. +.IP "\fB\-\-extdirs=\fR\fIpath\fR" 4 +.IX Item "--extdirs=path" +For each directory in the \fIpath\fR, place the contents of that +directory at the end of the class path. +.IP "\fB\s-1CLASSPATH\s0\fR" 4 +.IX Item "CLASSPATH" +This is an environment variable which holds a list of paths. +.PP +The final class path is constructed like so: +.IP "\(bu" 4 +First come all directories specified via \f(CW\*(C`\-I\*(C'\fR. +.IP "\(bu" 4 +If \fB\-\-classpath\fR is specified, its value is appended. +Otherwise, if the \f(CW\*(C`CLASSPATH\*(C'\fR environment variable is specified, +then its value is appended. +Otherwise, the current directory (\f(CW"."\fR) is appended. +.IP "\(bu" 4 +If \f(CW\*(C`\-\-bootclasspath\*(C'\fR was specified, append its value. +Otherwise, append the built-in system directory, \fIlibgcj.jar\fR. +.IP "\(bu" 4 +Finally, if \f(CW\*(C`\-\-extdirs\*(C'\fR was specified, append the contents of the +specified directories at the end of the class path. Otherwise, append +the contents of the built-in extdirs at \f(CW\*(C`$(prefix)/share/java/ext\*(C'\fR. +.PP +The classfile built by \fBgcj\fR for the class \f(CW\*(C`java.lang.Object\*(C'\fR +(and placed in \f(CW\*(C`libgcj.jar\*(C'\fR) contains a special zero length +attribute \f(CW\*(C`gnu.gcj.gcj\-compiled\*(C'\fR. The compiler looks for this +attribute when loading \f(CW\*(C`java.lang.Object\*(C'\fR and will report an error +if it isn't found, unless it compiles to bytecode (the option +\&\f(CW\*(C`\-fforce\-classes\-archive\-check\*(C'\fR can be used to override this +behavior in this particular case.) +.IP "\fB\-fforce\-classes\-archive\-check\fR" 4 +.IX Item "-fforce-classes-archive-check" +This forces the compiler to always check for the special zero length +attribute \f(CW\*(C`gnu.gcj.gcj\-compiled\*(C'\fR in \f(CW\*(C`java.lang.Object\*(C'\fR and +issue an error if it isn't found. +.IP "\fB\-fsource=\fR\fI\s-1VERSION\s0\fR" 4 +.IX Item "-fsource=VERSION" +This option is used to choose the source version accepted by +\&\fBgcj\fR. The default is \fB1.5\fR. +.Sh "Encodings" +.IX Subsection "Encodings" +The Java programming language uses Unicode throughout. In an effort to +integrate well with other locales, \fBgcj\fR allows \fI.java\fR files +to be written using almost any encoding. \fBgcj\fR knows how to +convert these encodings into its internal encoding at compile time. +.PP +You can use the \f(CW\*(C`\-\-encoding=\f(CINAME\f(CW\*(C'\fR option to specify an +encoding (of a particular character set) to use for source files. If +this is not specified, the default encoding comes from your current +locale. If your host system has insufficient locale support, then +\&\fBgcj\fR assumes the default encoding to be the \fB\s-1UTF\-8\s0\fR encoding +of Unicode. +.PP +To implement \f(CW\*(C`\-\-encoding\*(C'\fR, \fBgcj\fR simply uses the host +platform's \f(CW\*(C`iconv\*(C'\fR conversion routine. This means that in practice +\&\fBgcj\fR is limited by the capabilities of the host platform. +.PP +The names allowed for the argument \f(CW\*(C`\-\-encoding\*(C'\fR vary from platform +to platform (since they are not standardized anywhere). However, +\&\fBgcj\fR implements the encoding named \fB\s-1UTF\-8\s0\fR internally, so if +you choose to use this for your source files you can be assured that it +will work on every host. +.Sh "Warnings" +.IX Subsection "Warnings" +\&\fBgcj\fR implements several warnings. As with other generic +\&\fBgcc\fR warnings, if an option of the form \f(CW\*(C`\-Wfoo\*(C'\fR enables a +warning, then \f(CW\*(C`\-Wno\-foo\*(C'\fR will disable it. Here we've chosen to +document the form of the warning which will have an effect \*(-- the +default being the opposite of what is listed. +.IP "\fB\-Wredundant\-modifiers\fR" 4 +.IX Item "-Wredundant-modifiers" +With this flag, \fBgcj\fR will warn about redundant modifiers. For +instance, it will warn if an interface method is declared \f(CW\*(C`public\*(C'\fR. +.IP "\fB\-Wextraneous\-semicolon\fR" 4 +.IX Item "-Wextraneous-semicolon" +This causes \fBgcj\fR to warn about empty statements. Empty statements +have been deprecated. +.IP "\fB\-Wno\-out\-of\-date\fR" 4 +.IX Item "-Wno-out-of-date" +This option will cause \fBgcj\fR not to warn when a source file is +newer than its matching class file. By default \fBgcj\fR will warn +about this. +.IP "\fB\-Wno\-deprecated\fR" 4 +.IX Item "-Wno-deprecated" +Warn if a deprecated class, method, or field is referred to. +.IP "\fB\-Wunused\fR" 4 +.IX Item "-Wunused" +This is the same as \fBgcc\fR's \f(CW\*(C`\-Wunused\*(C'\fR. +.IP "\fB\-Wall\fR" 4 +.IX Item "-Wall" +This is the same as \f(CW\*(C`\-Wredundant\-modifiers \-Wextraneous\-semicolon +\&\-Wunused\*(C'\fR. +.Sh "Linking" +.IX Subsection "Linking" +To turn a Java application into an executable program, +you need to link it with the needed libraries, just as for C or \*(C+. +The linker by default looks for a global function named \f(CW\*(C`main\*(C'\fR. +Since Java does not have global functions, and a +collection of Java classes may have more than one class with a +\&\f(CW\*(C`main\*(C'\fR method, you need to let the linker know which of those +\&\f(CW\*(C`main\*(C'\fR methods it should invoke when starting the application. +You can do that in any of these ways: +.IP "\(bu" 4 +Specify the class containing the desired \f(CW\*(C`main\*(C'\fR method +when you link the application, using the \f(CW\*(C`\-\-main\*(C'\fR flag, +described below. +.IP "\(bu" 4 +Link the Java package(s) into a shared library (dll) rather than an +executable. Then invoke the application using the \f(CW\*(C`gij\*(C'\fR program, +making sure that \f(CW\*(C`gij\*(C'\fR can find the libraries it needs. +.IP "\(bu" 4 +Link the Java packages(s) with the flag \f(CW\*(C`\-lgij\*(C'\fR, which links +in the \f(CW\*(C`main\*(C'\fR routine from the \f(CW\*(C`gij\*(C'\fR command. +This allows you to select the class whose \f(CW\*(C`main\*(C'\fR method you +want to run when you run the application. You can also use +other \f(CW\*(C`gij\*(C'\fR flags, such as \f(CW\*(C`\-D\*(C'\fR flags to set properties. +Using the \f(CW\*(C`\-lgij\*(C'\fR library (rather than the \f(CW\*(C`gij\*(C'\fR program +of the previous mechanism) has some advantages: it is compatible with +static linking, and does not require configuring or installing libraries. +.PP +These \f(CW\*(C`gij\*(C'\fR options relate to linking an executable: +.IP "\fB\-\-main=\fR\fI\s-1CLASSNAME\s0\fR" 4 +.IX Item "--main=CLASSNAME" +This option is used when linking to specify the name of the class whose +\&\f(CW\*(C`main\*(C'\fR method should be invoked when the resulting executable is +run. +.IP "\fB\-D\fR\fIname\fR\fB[=\fR\fIvalue\fR\fB]\fR" 4 +.IX Item "-Dname[=value]" +This option can only be used with \f(CW\*(C`\-\-main\*(C'\fR. It defines a system +property named \fIname\fR with value \fIvalue\fR. If \fIvalue\fR is not +specified then it defaults to the empty string. These system properties +are initialized at the program's startup and can be retrieved at runtime +using the \f(CW\*(C`java.lang.System.getProperty\*(C'\fR method. +.IP "\fB\-lgij\fR" 4 +.IX Item "-lgij" +Create an application whose command-line processing is that +of the \f(CW\*(C`gij\*(C'\fR command. +.Sp +This option is an alternative to using \f(CW\*(C`\-\-main\*(C'\fR; you cannot use both. +.IP "\fB\-static\-libgcj\fR" 4 +.IX Item "-static-libgcj" +This option causes linking to be done against a static version of the +libgcj runtime library. This option is only available if +corresponding linker support exists. +.Sp +\&\fBCaution:\fR Static linking of libgcj may cause essential parts +of libgcj to be omitted. Some parts of libgcj use reflection to load +classes at runtime. Since the linker does not see these references at +link time, it can omit the referred to classes. The result is usually +(but not always) a \f(CW\*(C`ClassNotFoundException\*(C'\fR being thrown at +runtime. Caution must be used when using this option. For more +details see: +<\fBhttp://gcc.gnu.org/wiki/Statically%20linking%20libgcj\fR> +.Sh "Code Generation" +.IX Subsection "Code Generation" +In addition to the many \fBgcc\fR options controlling code generation, +\&\fBgcj\fR has several options specific to itself. +.IP "\fB\-C\fR" 4 +.IX Item "-C" +This option is used to tell \fBgcj\fR to generate bytecode +(\fI.class\fR files) rather than object code. +.IP "\fB\-\-resource\fR \fIresource-name\fR" 4 +.IX Item "--resource resource-name" +This option is used to tell \fBgcj\fR to compile the contents of a +given file to object code so it may be accessed at runtime with the core +protocol handler as \fBcore:/\fR\fIresource-name\fR. Note that +\&\fIresource-name\fR is the name of the resource as found at runtime; for +instance, it could be used in a call to \f(CW\*(C`ResourceBundle.getBundle\*(C'\fR. +The actual file name to be compiled this way must be specified +separately. +.IP "\fB\-ftarget=\fR\fI\s-1VERSION\s0\fR" 4 +.IX Item "-ftarget=VERSION" +This can be used with \fB\-C\fR to choose the version of bytecode +emitted by \fBgcj\fR. The default is \fB1.5\fR. When not +generating bytecode, this option has no effect. +.IP "\fB\-d\fR \fIdirectory\fR" 4 +.IX Item "-d directory" +When used with \f(CW\*(C`\-C\*(C'\fR, this causes all generated \fI.class\fR files +to be put in the appropriate subdirectory of \fIdirectory\fR. By +default they will be put in subdirectories of the current working +directory. +.IP "\fB\-fno\-bounds\-check\fR" 4 +.IX Item "-fno-bounds-check" +By default, \fBgcj\fR generates code which checks the bounds of all +array indexing operations. With this option, these checks are omitted, which +can improve performance for code that uses arrays extensively. Note that this +can result in unpredictable behavior if the code in question actually does +violate array bounds constraints. It is safe to use this option if you are +sure that your code will never throw an \f(CW\*(C`ArrayIndexOutOfBoundsException\*(C'\fR. +.IP "\fB\-fno\-store\-check\fR" 4 +.IX Item "-fno-store-check" +Don't generate array store checks. When storing objects into arrays, a runtime +check is normally generated in order to ensure that the object is assignment +compatible with the component type of the array (which may not be known +at compile-time). With this option, these checks are omitted. This can +improve performance for code which stores objects into arrays frequently. +It is safe to use this option if you are sure your code will never throw an +\&\f(CW\*(C`ArrayStoreException\*(C'\fR. +.IP "\fB\-fjni\fR" 4 +.IX Item "-fjni" +With \fBgcj\fR there are two options for writing native methods: \s-1CNI\s0 +and \s-1JNI\s0. By default \fBgcj\fR assumes you are using \s-1CNI\s0. If you are +compiling a class with native methods, and these methods are implemented +using \s-1JNI\s0, then you must use \f(CW\*(C`\-fjni\*(C'\fR. This option causes +\&\fBgcj\fR to generate stubs which will invoke the underlying \s-1JNI\s0 +methods. +.IP "\fB\-fno\-assert\fR" 4 +.IX Item "-fno-assert" +Don't recognize the \f(CW\*(C`assert\*(C'\fR keyword. This is for compatibility +with older versions of the language specification. +.IP "\fB\-fno\-optimize\-static\-class\-initialization\fR" 4 +.IX Item "-fno-optimize-static-class-initialization" +When the optimization level is greater or equal to \f(CW\*(C`\-O2\*(C'\fR, +\&\fBgcj\fR will try to optimize the way calls into the runtime are made +to initialize static classes upon their first use (this optimization +isn't carried out if \f(CW\*(C`\-C\*(C'\fR was specified.) When compiling to native +code, \f(CW\*(C`\-fno\-optimize\-static\-class\-initialization\*(C'\fR will turn this +optimization off, regardless of the optimization level in use. +.IP "\fB\-\-disable\-assertions[=\fR\fIclass-or-package\fR\fB]\fR" 4 +.IX Item "--disable-assertions[=class-or-package]" +Don't include code for checking assertions in the compiled code. +If \f(CW\*(C`=\f(CIclass\-or\-package\f(CW\*(C'\fR is missing disables assertion code +generation for all classes, unless overridden by a more +specific \f(CW\*(C`\-\-enable\-assertions\*(C'\fR flag. +If \fIclass-or-package\fR is a class name, only disables generating +assertion checks within the named class or its inner classes. +If \fIclass-or-package\fR is a package name, disables generating +assertion checks within the named package or a subpackage. +.Sp +By default, assertions are enabled when generating class files +or when not optimizing, and disabled when generating optimized binaries. +.IP "\fB\-\-enable\-assertions[=\fR\fIclass-or-package\fR\fB]\fR" 4 +.IX Item "--enable-assertions[=class-or-package]" +Generates code to check assertions. The option is perhaps misnamed, +as you still need to turn on assertion checking at run-time, +and we don't support any easy way to do that. +So this flag isn't very useful yet, except to partially override +\&\f(CW\*(C`\-\-disable\-assertions\*(C'\fR. +.IP "\fB\-findirect\-dispatch\fR" 4 +.IX Item "-findirect-dispatch" +\&\fBgcj\fR has a special binary compatibility \s-1ABI\s0, which is enabled +by the \f(CW\*(C`\-findirect\-dispatch\*(C'\fR option. In this mode, the code +generated by \fBgcj\fR honors the binary compatibility guarantees +in the Java Language Specification, and the resulting object files do +not need to be directly linked against their dependencies. Instead, +all dependencies are looked up at runtime. This allows free mixing of +interpreted and compiled code. +.Sp +Note that, at present, \f(CW\*(C`\-findirect\-dispatch\*(C'\fR can only be used +when compiling \fI.class\fR files. It will not work when compiling +from source. \s-1CNI\s0 also does not yet work with the binary compatibility +\&\s-1ABI\s0. These restrictions will be lifted in some future release. +.Sp +However, if you compile \s-1CNI\s0 code with the standard \s-1ABI\s0, you can call +it from code built with the binary compatibility \s-1ABI\s0. +.IP "\fB\-fbootstrap\-classes\fR" 4 +.IX Item "-fbootstrap-classes" +This option can be use to tell \f(CW\*(C`libgcj\*(C'\fR that the compiled classes +should be loaded by the bootstrap loader, not the system class loader. +By default, if you compile a class and link it into an executable, it +will be treated as if it was loaded using the system class loader. +This is convenient, as it means that things like +\&\f(CW\*(C`Class.forName()\*(C'\fR will search \fB\s-1CLASSPATH\s0\fR to find the +desired class. +.IP "\fB\-freduced\-reflection\fR" 4 +.IX Item "-freduced-reflection" +This option causes the code generated by \fBgcj\fR to contain a +reduced amount of the class meta-data used to support runtime +reflection. The cost of this savings is the loss of +the ability to use certain reflection capabilities of the standard +Java runtime environment. When set all meta-data except for that +which is needed to obtain correct runtime semantics is eliminated. +.Sp +For code that does not use reflection (i.e. serialization, \s-1RMI\s0, \s-1CORBA\s0 +or call methods in the \f(CW\*(C`java.lang.reflect\*(C'\fR package), +\&\f(CW\*(C`\-freduced\-reflection\*(C'\fR will result in proper operation with a +savings in executable code size. +.Sp +\&\s-1JNI\s0 (\f(CW\*(C`\-fjni\*(C'\fR) and the binary compatibility \s-1ABI\s0 +(\f(CW\*(C`\-findirect\-dispatch\*(C'\fR) do not work properly without full +reflection meta-data. Because of this, it is an error to use these options +with \f(CW\*(C`\-freduced\-reflection\*(C'\fR. +.Sp +\&\fBCaution:\fR If there is no reflection meta-data, code that uses +a \f(CW\*(C`SecurityManager\*(C'\fR may not work properly. Also calling +\&\f(CW\*(C`Class.forName()\*(C'\fR may fail if the calling method has no +reflection meta-data. +.Sh "Configure-time Options" +.IX Subsection "Configure-time Options" +Some \fBgcj\fR code generations options affect the resulting \s-1ABI\s0, and +so can only be meaningfully given when \f(CW\*(C`libgcj\*(C'\fR, the runtime +package, is configured. \f(CW\*(C`libgcj\*(C'\fR puts the appropriate options from +this group into a \fBspec\fR file which is read by \fBgcj\fR. These +options are listed here for completeness; if you are using \f(CW\*(C`libgcj\*(C'\fR +then you won't want to touch these options. +.IP "\fB\-fuse\-boehm\-gc\fR" 4 +.IX Item "-fuse-boehm-gc" +This enables the use of the Boehm \s-1GC\s0 bitmap marking code. In particular +this causes \fBgcj\fR to put an object marking descriptor into each +vtable. +.IP "\fB\-fhash\-synchronization\fR" 4 +.IX Item "-fhash-synchronization" +By default, synchronization data (the data used for \f(CW\*(C`synchronize\*(C'\fR, +\&\f(CW\*(C`wait\*(C'\fR, and \f(CW\*(C`notify\*(C'\fR) is pointed to by a word in each object. +With this option \fBgcj\fR assumes that this information is stored in a +hash table and not in the object itself. +.IP "\fB\-fuse\-divide\-subroutine\fR" 4 +.IX Item "-fuse-divide-subroutine" +On some systems, a library routine is called to perform integer +division. This is required to get exception handling correct when +dividing by zero. +.IP "\fB\-fcheck\-references\fR" 4 +.IX Item "-fcheck-references" +On some systems it's necessary to insert inline checks whenever +accessing an object via a reference. On other systems you won't need +this because null pointer accesses are caught automatically by the +processor. +.SH "SEE ALSO" +.IX Header "SEE ALSO" +\&\fIgcc\fR\|(1), \fIgcjh\fR\|(1), \fIgjnih\fR\|(1), \fIgij\fR\|(1), \fIjcf\-dump\fR\|(1), \fIgfdl\fR\|(7), +and the Info entries for \fIgcj\fR and \fIgcc\fR. +.SH "COPYRIGHT" +.IX Header "COPYRIGHT" +Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc. +.PP +Permission is granted to copy, distribute and/or modify this document +under the terms of the \s-1GNU\s0 Free Documentation License, Version 1.2 or +any later version published by the Free Software Foundation; with no +Invariant Sections, the Front-Cover Texts being (a) (see below), and +with the Back-Cover Texts being (b) (see below). +A copy of the license is included in the +man page \fIgfdl\fR\|(7). +.PP +(a) The \s-1FSF\s0's Front-Cover Text is: +.PP +.Vb 1 +\& A GNU Manual +.Ve +.PP +(b) The \s-1FSF\s0's Back-Cover Text is: +.PP +.Vb 3 +\& You have freedom to copy and modify this GNU Manual, like GNU +\& software. Copies published by the Free Software Foundation raise +\& funds for GNU development. +.Ve