X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=ld%2Fld.texinfo;h=789e8940bba68427e333c5e3213f3cc03a200f66;hb=5435462c555ab99f8687efda29476de470ebcec1;hp=74e0b8711e19962da0853c3bdd49ca204c8072de;hpb=3c3bdf30e42268e6193693acd1dc66d2d1792536;p=deliverable%2Fbinutils-gdb.git diff --git a/ld/ld.texinfo b/ld/ld.texinfo index 74e0b8711e..789e8940bb 100644 --- a/ld/ld.texinfo +++ b/ld/ld.texinfo @@ -1,7 +1,7 @@ \input texinfo @setfilename ld.info @c Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, -@c 2001 Free Software Foundation, Inc. +@c 2001, 2002 Free Software Foundation, Inc. @syncodeindex ky cp @include configdoc.texi @c (configdoc.texi is generated by the Makefile) @@ -9,6 +9,10 @@ @c @smallbook +@macro gcctabopt{body} +@code{\body\} +@end macro + @c man begin NAME @ifset man @c Configure for the generation of man pages @@ -54,7 +58,7 @@ END-INFO-DIR-ENTRY This file documents the @sc{gnu} linker LD version @value{VERSION}. Copyright (C) 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, -2001 Free Software Foundation, Inc. +2001, 2002 Free Software Foundation, Inc. @ignore @@ -98,7 +102,7 @@ notice identical to this one except for the removal of this paragraph @vskip 0pt plus 1filll @c man begin COPYRIGHT -Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000 Free Software Foundation, Inc. +Copyright @copyright{} 1991, 92, 93, 94, 95, 96, 97, 98, 99, 2000, 2001 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 @@ -112,7 +116,7 @@ section entitled "GNU Free Documentation License". @end iftex @c FIXME: Talk about importance of *order* of args, cmds to linker! -@ifinfo +@ifnottex @node Top @top Using ld This file documents the @sc{gnu} linker ld version @value{VERSION}. @@ -152,7 +156,7 @@ section entitled "GNU Free Documentation License". * GNU Free Documentation License:: GNU Free Documentation License * Index:: Index @end menu -@end ifinfo +@end ifnottex @node Overview @chapter Overview @@ -162,7 +166,7 @@ section entitled "GNU Free Documentation License". @ifset man @c man begin SYNOPSIS -ld [ options ] objfile... +ld [@b{options}] @var{objfile} @dots{} @c man end @c man begin SEEALSO @@ -174,25 +178,25 @@ the Info entries for @file{binutils} and @c man begin DESCRIPTION -@code{ld} combines a number of object and archive files, relocates +@command{ld} combines a number of object and archive files, relocates their data and ties up symbol references. Usually the last step in -compiling a program is to run @code{ld}. +compiling a program is to run @command{ld}. -@code{ld} accepts Linker Command Language files written in +@command{ld} accepts Linker Command Language files written in a superset of AT&T's Link Editor Command Language syntax, to provide explicit and total control over the linking process. @ifset man @c For the man only This man page does not describe the command language; see the -@code{ld} entry in @code{info}, or the manual +@command{ld} entry in @code{info}, or the manual ld: the GNU linker, for full details on the command language and on other aspects of the GNU linker. @end ifset @ifclear SingleFormat -This version of @code{ld} uses the general purpose BFD libraries -to operate on object files. This allows @code{ld} to read, combine, and +This version of @command{ld} uses the general purpose BFD libraries +to operate on object files. This allows @command{ld} to read, combine, and write object files in many different formats---for example, COFF or @code{a.out}. Different formats may be linked together to produce any available kind of object file. @xref{BFD}, for more information. @@ -201,7 +205,7 @@ available kind of object file. @xref{BFD}, for more information. Aside from its flexibility, the @sc{gnu} linker is more helpful than other linkers in providing diagnostic information. Many linkers abandon execution immediately upon encountering an error; whenever possible, -@code{ld} continues executing, allowing you to identify other errors +@command{ld} continues executing, allowing you to identify other errors (or, in some cases, to get an output file in spite of the error). @c man end @@ -211,7 +215,7 @@ execution immediately upon encountering an error; whenever possible, @c man begin DESCRIPTION -The @sc{gnu} linker @code{ld} is meant to cover a broad range of situations, +The @sc{gnu} linker @command{ld} is meant to cover a broad range of situations, and to be as compatible as possible with other linkers. As a result, you have many choices to control its behavior. @@ -235,7 +239,7 @@ you have many choices to control its behavior. The linker supports a plethora of command-line options, but in actual practice few of them are used in any particular context. @cindex standard Unix system -For instance, a frequent use of @code{ld} is to link standard Unix +For instance, a frequent use of @command{ld} is to link standard Unix object files on a standard, supported Unix system. On such a system, to link a file @code{hello.o}: @@ -243,12 +247,12 @@ link a file @code{hello.o}: ld -o @var{output} /lib/crt0.o hello.o -lc @end smallexample -This tells @code{ld} to produce a file called @var{output} as the +This tells @command{ld} to produce a file called @var{output} as the result of linking the file @code{/lib/crt0.o} with @code{hello.o} and the library @code{libc.a}, which will come from the standard search directories. (See the discussion of the @samp{-l} option below.) -Some of the command-line options to @code{ld} may be specified at any +Some of the command-line options to @command{ld} may be specified at any point in the command line. However, options which refer to files, such as @samp{-l} or @samp{-T}, cause the file to be read at the point at which the option appears in the command line, relative to the object @@ -277,10 +281,8 @@ linker script or the one specified by using @samp{-T}). This feature permits the linker to link against a file which appears to be an object or an archive, but actually merely defines some symbol values, or uses @code{INPUT} or @code{GROUP} to load other objects. Note that -specifying a script in this way should only be used to augment the main -linker script; if you want to use some command that logically can only -appear once, such as the @code{SECTIONS} or @code{MEMORY} command, you -must replace the default linker script using the @samp{-T} option. +specifying a script in this way merely augments the main linker script; +use the @samp{-T} option to replace the default linker script entirely. @xref{Scripts}. For options whose names are a single letter, @@ -319,7 +321,7 @@ silently drop the linker options, resulting in a bad link. Here is a table of the generic command line switches accepted by the GNU linker: -@table @code +@table @gcctabopt @kindex -a@var{keyword} @item -a@var{keyword} This option is supported for HP/UX compatibility. The @var{keyword} @@ -334,14 +336,14 @@ to @samp{-Bdynamic}. This option may be used any number of times. @item -A@var{architecture} @kindex --architecture=@var{arch} @itemx --architecture=@var{architecture} -In the current release of @code{ld}, this option is useful only for the -Intel 960 family of architectures. In that @code{ld} configuration, the +In the current release of @command{ld}, this option is useful only for the +Intel 960 family of architectures. In that @command{ld} configuration, the @var{architecture} argument identifies the particular architecture in the 960 family, enabling some safeguards and modifying the -archive-library search path. @xref{i960,,@code{ld} and the Intel 960 +archive-library search path. @xref{i960,,@command{ld} and the Intel 960 family}, for details. -Future releases of @code{ld} may support similar functionality for +Future releases of @command{ld} may support similar functionality for other architecture families. @end ifset @@ -353,12 +355,12 @@ other architecture families. @cindex input format @item -b @var{input-format} @itemx --format=@var{input-format} -@code{ld} may be configured to support more than one kind of object -file. If your @code{ld} is configured this way, you can use the +@command{ld} may be configured to support more than one kind of object +file. If your @command{ld} is configured this way, you can use the @samp{-b} option to specify the binary format for input object files -that follow this option on the command line. Even when @code{ld} is +that follow this option on the command line. Even when @command{ld} is configured to support alternative object formats, you don't usually need -to specify this, as @code{ld} should be configured to expect as a +to specify this, as @command{ld} should be configured to expect as a default input format the most usual format on each machine. @var{input-format} is a text string, the name of a particular format supported by the BFD libraries. (You can list the available binary @@ -388,7 +390,7 @@ see @ref{Format Commands}. @cindex compatibility, MRI @item -c @var{MRI-commandfile} @itemx --mri-script=@var{MRI-commandfile} -For compatibility with linkers produced by MRI, @code{ld} accepts script +For compatibility with linkers produced by MRI, @command{ld} accepts script files written in an alternate, restricted command language, described in @ifclear man @ref{MRI,,MRI Compatible Script Files}. @@ -398,8 +400,8 @@ the MRI Compatible Script Files section of GNU ld documentation. @end ifset Introduce MRI script files with the option @samp{-c}; use the @samp{-T} option to run linker -scripts written in the general-purpose @code{ld} scripting language. -If @var{MRI-cmdfile} does not exist, @code{ld} looks for it in the directories +scripts written in the general-purpose @command{ld} scripting language. +If @var{MRI-cmdfile} does not exist, @command{ld} looks for it in the directories specified by any @samp{-L} options. @cindex common allocation @@ -500,12 +502,12 @@ found in the shared object @var{name}. Thus the filter object can be used to select a subset of the symbols provided by the object @var{name}. -Some older linkers used the @code{-F} option throughout a compilation +Some older linkers used the @option{-F} option throughout a compilation toolchain for specifying object-file format for both input and output object files. The @sc{gnu} linker uses other mechanisms for this -purpose: the @code{-b}, @code{--format}, @code{--oformat} options, the +purpose: the @option{-b}, @option{--format}, @option{--oformat} options, the @code{TARGET} command in linker scripts, and the @code{GNUTARGET} -environment variable. The @sc{gnu} linker will ignore the @code{-F} +environment variable. The @sc{gnu} linker will ignore the @option{-F} option when not creating an ELF shared object. @cindex finalization function @@ -560,13 +562,13 @@ function to call. @item -l@var{archive} @itemx --library=@var{archive} Add archive file @var{archive} to the list of files to link. This -option may be used any number of times. @code{ld} will search its +option may be used any number of times. @command{ld} will search its path-list for occurrences of @code{lib@var{archive}.a} for every @var{archive} specified. -On systems which support shared libraries, @code{ld} may also search for +On systems which support shared libraries, @command{ld} may also search for libraries with extensions other than @code{.a}. Specifically, on ELF -and SunOS systems, @code{ld} will search a directory for a library with +and SunOS systems, @command{ld} will search a directory for a library with an extension of @code{.so} before searching for one with an extension of @code{.a}. By convention, a @code{.so} extension indicates a shared library. @@ -578,14 +580,14 @@ command line, the linker will include the appropriate file(s) from the archive. However, an undefined symbol in an object appearing later on the command line will not cause the linker to search the archive again. -See the @code{-(} option for a way to force the linker to search +See the @option{-(} option for a way to force the linker to search archives multiple times. You may list the same archive multiple times on the command line. @ifset GENERIC This type of archive searching is standard for Unix linkers. However, -if you are using @code{ld} on AIX, note that it is different from the +if you are using @command{ld} on AIX, note that it is different from the behaviour of the AIX linker. @end ifset @@ -594,17 +596,17 @@ behaviour of the AIX linker. @kindex --library-path=@var{dir} @item -L@var{searchdir} @itemx --library-path=@var{searchdir} -Add path @var{searchdir} to the list of paths that @code{ld} will search -for archive libraries and @code{ld} control scripts. You may use this +Add path @var{searchdir} to the list of paths that @command{ld} will search +for archive libraries and @command{ld} control scripts. You may use this option any number of times. The directories are searched in the order in which they are specified on the command line. Directories specified on the command line are searched before the default directories. All -@code{-L} options apply to all @code{-l} options, regardless of the +@option{-L} options apply to all @option{-l} options, regardless of the order in which the options appear. @ifset UsesEnvVars The default set of paths searched (without being specified with -@samp{-L}) depends on which emulation mode @code{ld} is using, and in +@samp{-L}) depends on which emulation mode @command{ld} is using, and in some cases also on how it was configured. @xref{Environment}. @end ifset @@ -666,14 +668,14 @@ style magic numbers, mark the output as @code{OMAGIC}. @cindex naming the output file @item -o @var{output} @itemx --output=@var{output} -Use @var{output} as the name for the program produced by @code{ld}; if this +Use @var{output} as the name for the program produced by @command{ld}; if this option is not specified, the name @file{a.out} is used by default. The script command @code{OUTPUT} can also specify the output file name. @kindex -O @var{level} @cindex generating optimized output @item -O @var{level} -If @var{level} is a numeric values greater than zero @code{ld} optimizes +If @var{level} is a numeric values greater than zero @command{ld} optimizes the output. This might take significantly longer and therefore probably should only be enabled for the final binary. @@ -687,6 +689,8 @@ Post link analysis and optimization tools may need this information in order to perform correct modifications of executables. This results in larger executables. +This option is currently only supported on ELF platforms. + @cindex partial link @cindex relocatable output @kindex -r @@ -694,11 +698,11 @@ in larger executables. @item -r @itemx --relocateable Generate relocatable output---i.e., generate an output file that can in -turn serve as input to @code{ld}. This is often called @dfn{partial +turn serve as input to @command{ld}. This is often called @dfn{partial linking}. As a side effect, in environments that support standard Unix magic numbers, this option also sets the output file's magic number to @code{OMAGIC}. -@c ; see @code{-N}. +@c ; see @option{-N}. If this option is not specified, an absolute file is produced. When linking C++ programs, this option @emph{will not} resolve references to constructors; to do that, use @samp{-Ur}. @@ -721,9 +725,9 @@ relocate it or include it in the output. This allows your output file to refer symbolically to absolute locations of memory defined in other programs. You may use this option more than once. -For compatibility with other ELF linkers, if the @code{-R} option is +For compatibility with other ELF linkers, if the @option{-R} option is followed by a directory name, rather than a file name, it is treated as -the @code{-rpath} option. +the @option{-rpath} option. @kindex -s @kindex --strip-all @@ -744,7 +748,7 @@ Omit debugger symbol information (but not all symbols) from the output file. @cindex input files, displaying @item -t @itemx --trace -Print the names of the input files as @code{ld} processes them. +Print the names of the input files as @command{ld} processes them. @kindex -T @var{script} @kindex --script=@var{script} @@ -752,14 +756,12 @@ Print the names of the input files as @code{ld} processes them. @item -T @var{scriptfile} @itemx --script=@var{scriptfile} Use @var{scriptfile} as the linker script. This script replaces -@code{ld}'s default linker script (rather than adding to it), so +@command{ld}'s default linker script (rather than adding to it), so @var{commandfile} must specify everything necessary to describe the -output file. You must use this option if you want to use a command -which can only appear once in a linker script, such as the -@code{SECTIONS} or @code{MEMORY} command. @xref{Scripts}. If -@var{scriptfile} does not exist in the current directory, @code{ld} -looks for it in the directories specified by any preceding @samp{-L} -options. Multiple @samp{-T} options accumulate. +output file. @xref{Scripts}. If @var{scriptfile} does not exist in +the current directory, @code{ld} looks for it in the directories +specified by any preceding @samp{-L} options. Multiple @samp{-T} +options accumulate. @kindex -u @var{symbol} @kindex --undefined=@var{symbol} @@ -777,7 +779,7 @@ option is equivalent to the @code{EXTERN} linker script command. @item -Ur For anything other than C++ programs, this option is equivalent to @samp{-r}: it generates relocatable output---i.e., an output file that can in -turn serve as input to @code{ld}. When linking C++ programs, @samp{-Ur} +turn serve as input to @command{ld}. When linking C++ programs, @samp{-Ur} @emph{does} resolve references to constructors, unlike @samp{-r}. It does not work to use @samp{-Ur} on files that were themselves linked with @samp{-Ur}; once the constructor table has been built, it cannot @@ -801,7 +803,7 @@ in a linker script. @item -v @itemx --version @itemx -V -Display the version number for @code{ld}. The @code{-V} option also +Display the version number for @command{ld}. The @option{-V} option also lists the supported emulations. @kindex -x @@ -857,6 +859,7 @@ of this object will ignore any default library search paths. @code{now} marks the object with the non-lazy runtime binding. @code{origin} marks the object may contain $ORIGIN. @code{defs} disallows undefined symbols. +@code{muldefs} allows multiple definitions. @code{combreloc} combines multiple reloc sections and sorts them to make dynamic symbol lookup caching possible. @code{nocombreloc} disables multiple reloc sections combining. @@ -897,14 +900,14 @@ for which shared libraries are supported. This option is normally the default on such platforms. The different variants of this option are for compatibility with various systems. You may use this option multiple times on the command line: it affects library searching for -@code{-l} options which follow it. +@option{-l} options which follow it. @kindex -Bgroup @item -Bgroup Set the @code{DF_1_GROUP} flag in the @code{DT_FLAGS_1} entry in the dynamic section. This causes the runtime linker to handle lookups in this object and its dependencies to be performed only inside the group. -@code{--no-undefined} is implied. This option is only meaningful on ELF +@option{--no-undefined} is implied. This option is only meaningful on ELF platforms which support shared libraries. @kindex -Bstatic @@ -919,7 +922,7 @@ Do not link against shared libraries. This is only meaningful on platforms for which shared libraries are supported. The different variants of this option are for compatibility with various systems. You may use this option multiple times on the command line: it affects -library searching for @code{-l} options which follow it. +library searching for @option{-l} options which follow it. @kindex -Bsymbolic @item -Bsymbolic @@ -1064,10 +1067,10 @@ Print a link map to the file @var{mapfile}. See the description of the @cindex memory usage @kindex --no-keep-memory @item --no-keep-memory -@code{ld} normally optimizes for speed over memory usage by caching the -symbol tables of input files in memory. This option tells @code{ld} to +@command{ld} normally optimizes for speed over memory usage by caching the +symbol tables of input files in memory. This option tells @command{ld} to instead optimize for memory usage, by rereading the symbol tables as -necessary. This may be required if @code{ld} runs out of memory space +necessary. This may be required if @command{ld} runs out of memory space while linking a large executable. @kindex --no-undefined @@ -1078,6 +1081,14 @@ Normally when creating a non-symbolic shared library, undefined symbols are allowed and left to be resolved by the runtime loader. These options disallows such undefined symbols. +@kindex --allow-multiple-definition +@kindex -z muldefs +@item --allow-multiple-definition +@itemx -z muldefs +Normally when a symbol is defined multiple times, the linker will +report a fatal error. These options allow multiple definitions and the +first definition will be used. + @kindex --allow-shlib-undefined @item --allow-shlib-undefined Allow undefined symbols in shared objects even when --no-undefined is @@ -1091,19 +1102,25 @@ select which function is most appropriate for the current architecture. I.E. dynamically select an appropriate memset function. Apparently it is also normal for HPPA shared libraries to have undefined symbols. +@kindex --no-undefined-version +@item --no-undefined-version +Normally when a symbol has an undefined version, the linker will ignore +it. This option disallows symbols with undefined version and a fatal error +will be issued instead. + @kindex --no-warn-mismatch @item --no-warn-mismatch -Normally @code{ld} will give an error if you try to link together input +Normally @command{ld} will give an error if you try to link together input files that are mismatched for some reason, perhaps because they have been compiled for different processors or for different endiannesses. -This option tells @code{ld} that it should silently permit such possible +This option tells @command{ld} that it should silently permit such possible errors. This option should only be used with care, in cases when you have taken some special action that ensures that the linker errors are inappropriate. @kindex --no-whole-archive @item --no-whole-archive -Turn off the effect of the @code{--whole-archive} option for subsequent +Turn off the effect of the @option{--whole-archive} option for subsequent archive files. @cindex output file after errors @@ -1114,14 +1131,20 @@ Normally, the linker will not produce an output file if it encounters errors during the link process; it exits without writing an output file when it issues any error whatsoever. +@kindex -nostdlib +@item -nostdlib +Only search library directories explicitly specified on the +command line. Library directories specified in linker scripts +(including linker scripts specified on the command line) are ignored. + @ifclear SingleFormat @kindex --oformat @item --oformat @var{output-format} -@code{ld} may be configured to support more than one kind of object -file. If your @code{ld} is configured this way, you can use the +@command{ld} may be configured to support more than one kind of object +file. If your @command{ld} is configured this way, you can use the @samp{--oformat} option to specify the binary format for the output -object file. Even when @code{ld} is configured to support alternative -object formats, you don't usually need to specify this, as @code{ld} +object file. Even when @command{ld} is configured to support alternative +object formats, you don't usually need to specify this, as @command{ld} should be configured to produce as a default output format the most usual format on each machine. @var{output-format} is a text string, the name of a particular format supported by the BFD libraries. (You can @@ -1147,10 +1170,10 @@ An option with machine dependent effects. This option is only supported on a few targets. @end ifset @ifset H8300 -@xref{H8/300,,@code{ld} and the H8/300}. +@xref{H8/300,,@command{ld} and the H8/300}. @end ifset @ifset I960 -@xref{i960,, @code{ld} and the Intel 960 family}. +@xref{i960,, @command{ld} and the Intel 960 family}. @end ifset @@ -1195,26 +1218,26 @@ line. It overrides @samp{-s} and @samp{-S}. @cindex runtime library search path @kindex -rpath Add a directory to the runtime library search path. This is used when -linking an ELF executable with shared objects. All @code{-rpath} +linking an ELF executable with shared objects. All @option{-rpath} arguments are concatenated and passed to the runtime linker, which uses -them to locate shared objects at runtime. The @code{-rpath} option is +them to locate shared objects at runtime. The @option{-rpath} option is also used when locating shared objects which are needed by shared objects explicitly included in the link; see the description of the -@code{-rpath-link} option. If @code{-rpath} is not used when linking an +@option{-rpath-link} option. If @option{-rpath} is not used when linking an ELF executable, the contents of the environment variable @code{LD_RUN_PATH} will be used if it is defined. -The @code{-rpath} option may also be used on SunOS. By default, on +The @option{-rpath} option may also be used on SunOS. By default, on SunOS, the linker will form a runtime search patch out of all the -@code{-L} options it is given. If a @code{-rpath} option is used, the -runtime search path will be formed exclusively using the @code{-rpath} -options, ignoring the @code{-L} options. This can be useful when using -gcc, which adds many @code{-L} options which may be on NFS mounted +@option{-L} options it is given. If a @option{-rpath} option is used, the +runtime search path will be formed exclusively using the @option{-rpath} +options, ignoring the @option{-L} options. This can be useful when using +gcc, which adds many @option{-L} options which may be on NFS mounted filesystems. -For compatibility with other ELF linkers, if the @code{-R} option is +For compatibility with other ELF linkers, if the @option{-R} option is followed by a directory name, rather than a file name, it is treated as -the @code{-rpath} option. +the @option{-rpath} option. @end ifset @ifset GENERIC @@ -1228,9 +1251,9 @@ of the input files. When the linker encounters such a dependency when doing a non-shared, non-relocatable link, it will automatically try to locate the required shared library and include it in the link, if it is not included -explicitly. In such a case, the @code{-rpath-link} option +explicitly. In such a case, the @option{-rpath-link} option specifies the first set of directories to search. The -@code{-rpath-link} option may specify a sequence of directory names +@option{-rpath-link} option may specify a sequence of directory names either by specifying a list of names separated by colons, or by appearing multiple times. @@ -1243,20 +1266,20 @@ The linker uses the following search paths to locate required shared libraries. @enumerate @item -Any directories specified by @code{-rpath-link} options. +Any directories specified by @option{-rpath-link} options. @item -Any directories specified by @code{-rpath} options. The difference -between @code{-rpath} and @code{-rpath-link} is that directories -specified by @code{-rpath} options are included in the executable and -used at runtime, whereas the @code{-rpath-link} option is only effective +Any directories specified by @option{-rpath} options. The difference +between @option{-rpath} and @option{-rpath-link} is that directories +specified by @option{-rpath} options are included in the executable and +used at runtime, whereas the @option{-rpath-link} option is only effective at link time. It is for the native linker only. @item -On an ELF system, if the @code{-rpath} and @code{rpath-link} options +On an ELF system, if the @option{-rpath} and @code{rpath-link} options were not used, search the contents of the environment variable @code{LD_RUN_PATH}. It is for the native linker only. @item -On SunOS, if the @code{-rpath} option was not used, search any -directories specified using @code{-L} options. +On SunOS, if the @option{-rpath} option was not used, search any +directories specified using @option{-L} options. @item For a native linker, the contents of the environment variable @code{LD_LIBRARY_PATH}. @@ -1283,12 +1306,12 @@ warning and continue with the link. @cindex shared libraries Create a shared library. This is currently only supported on ELF, XCOFF and SunOS platforms. On SunOS, the linker will automatically create a -shared library if the @code{-e} option is not used and there are +shared library if the @option{-e} option is not used and there are undefined symbols in the link. @item --sort-common @kindex --sort-common -This option tells @code{ld} to sort the common symbols by size when it +This option tells @command{ld} to sort the common symbols by size when it places them in the appropriate output sections. First come all the one byte symbols, then all the two byte, then all the four byte, and then everything else. This is to prevent gaps between symbols due to @@ -1296,7 +1319,7 @@ alignment constraints. @kindex --split-by-file @item --split-by-file [@var{size}] -Similar to @code{--split-by-reloc} but creates a new output section for +Similar to @option{--split-by-reloc} but creates a new output section for each input file when @var{size} is reached. @var{size} defaults to a size of 1 if not given. @@ -1321,16 +1344,16 @@ as execution time and memory usage. @kindex --traditional-format @cindex traditional format @item --traditional-format -For some targets, the output of @code{ld} is different in some ways from -the output of some existing linker. This switch requests @code{ld} to +For some targets, the output of @command{ld} is different in some ways from +the output of some existing linker. This switch requests @command{ld} to use the traditional format instead. @cindex dbx -For example, on SunOS, @code{ld} combines duplicate entries in the +For example, on SunOS, @command{ld} combines duplicate entries in the symbol string table. This can reduce the size of an output file with full debugging information by over 30 percent. Unfortunately, the SunOS @code{dbx} program can not read the resulting program (@code{gdb} has no -trouble). The @samp{--traditional-format} switch tells @code{ld} to not +trouble). The @samp{--traditional-format} switch tells @command{ld} to not combine duplicate entries. @kindex --section-start @var{sectionname}=@var{org} @@ -1362,7 +1385,7 @@ for compatibility with other linkers, you may omit the leading @cindex verbose @item --dll-verbose @itemx --verbose -Display the version number for @code{ld} and list the linker emulations +Display the version number for @command{ld} and list the linker emulations supported. Display which input files can and cannot be opened. Display the linker script being used by the linker. @@ -1501,15 +1524,15 @@ the section (@pxref{SECTIONS}). @cindex including an entire archive @item --whole-archive For each archive mentioned on the command line after the -@code{--whole-archive} option, include every object file in the archive +@option{--whole-archive} option, include every object file in the archive in the link, rather than searching the archive for the required object files. This is normally used to turn an archive file into a shared library, forcing every object to be included in the resulting shared library. This option may be used more than once. Two notes when using this option from gcc: First, gcc doesn't know -about this option, so you have to use @code{-Wl,-whole-archive}. -Second, don't forget to use @code{-Wl,-no-whole-archive} after your +about this option, so you have to use @option{-Wl,-whole-archive}. +Second, don't forget to use @option{-Wl,-no-whole-archive} after your list of archives, because gcc will add its own list of archives to your link and you may not want this flag to affect those as well. @@ -1536,13 +1559,13 @@ __wrap_malloc (int c) @} @end smallexample -If you link other code with this file using @code{--wrap malloc}, then +If you link other code with this file using @option{--wrap malloc}, then all calls to @code{malloc} will call the function @code{__wrap_malloc} instead. The call to @code{__real_malloc} in @code{__wrap_malloc} will call the real @code{malloc} function. You may wish to provide a @code{__real_malloc} function as well, so that -links without the @code{--wrap} option will succeed. If you do this, +links without the @option{--wrap} option will succeed. If you do this, you should not put the definition of @code{__real_malloc} in the same file as @code{__wrap_malloc}; if you do, the assembler may resolve the call before the linker has a chance to wrap it to @code{malloc}. @@ -1553,8 +1576,8 @@ call before the linker has a chance to wrap it to @code{malloc}. @itemx --disable-new-dtags This linker can create the new dynamic tags in ELF. But the older ELF systems may not understand them. If you specify -@code{--enable-new-dtags}, the dynamic tags will be created as needed. -If you specify @code{--disable-new-dtags}, no new dynamic tags will be +@option{--enable-new-dtags}, the dynamic tags will be created as needed. +If you specify @option{--disable-new-dtags}, no new dynamic tags will be created. By default, the new dynamic tags are not created. Note that those options are only available for ELF systems. @@ -1566,7 +1589,7 @@ those options are only available for ELF systems. @c man begin OPTIONS -The i386 PE linker supports the @code{-shared} option, which causes +The i386 PE linker supports the @option{-shared} option, which causes the output to be a dynamically linked library (DLL) instead of a normal executable. You should name the output @code{*.dll} when you use this option. In addition, the linker fully supports the standard @@ -1580,7 +1603,7 @@ support additional command line options that are specific to the i386 PE target. Options that take values may be separated from their values by either a space or an equals sign. -@table @code +@table @gcctabopt @kindex --add-stdcall-alias @item --add-stdcall-alias @@ -1596,7 +1619,7 @@ addresses of all the relocations needed for generating DLLs with @kindex --dll @item --dll Create a DLL instead of a regular executable. You may also use -@code{-shared} or specify a @code{LIBRARY} in a given @code{.def} +@option{-shared} or specify a @code{LIBRARY} in a given @code{.def} file. @kindex --enable-stdcall-fixup @@ -1612,9 +1635,9 @@ undefined symbol @code{_foo} might be linked to the function to the function @code{_bar}. When the linker does this, it prints a warning, since it normally should have failed to link, but sometimes import libraries generated from third-party dlls may need this feature -to be usable. If you specify @code{--enable-stdcall-fixup}, this +to be usable. If you specify @option{--enable-stdcall-fixup}, this feature is fully enabled and warnings are not printed. If you specify -@code{--disable-stdcall-fixup}, this feature is disabled and such +@option{--disable-stdcall-fixup}, this feature is disabled and such mismatches are considered to be errors. @cindex DLLs, creating @@ -1648,6 +1671,14 @@ These cygwin-excludes are: @code{_cygwin_dll_entry@@12}, Specifies a list of symbols which should not be automatically exported. The symbol names may be delimited by commas or colons. +@kindex --exclude-libs +@item --exclude-libs @var{lib},@var{lib},... +Specifies a list of archive libraries from which symbols should not be automatically +exported. The library names may be delimited by commas or colons. Specifying +@code{--exclude-libs ALL} excludes symbols in all archive libraries from +automatic export. Symbols explicitly listed in a .def file are still exported, +regardless of this option. + @kindex --file-alignment @item --file-alignment Specify the file alignment. Sections in the file will always begin at @@ -1901,7 +1932,7 @@ subsystem version also. @c man begin ENVIRONMENT -You can change the behavior of @code{ld} with the environment variables +You can change the behavior of @command{ld} with the environment variables @code{GNUTARGET}, @code{LDEMULATION}, and @code{COLLECT_NO_DEMANGLE}. @kindex GNUTARGET @@ -1909,7 +1940,7 @@ You can change the behavior of @code{ld} with the environment variables @code{GNUTARGET} determines the input-file object format if you don't use @samp{-b} (or its synonym @samp{--format}). Its value should be one of the BFD names for an input format (@pxref{BFD}). If there is no -@code{GNUTARGET} in the environment, @code{ld} uses the natural format +@code{GNUTARGET} in the environment, @command{ld} uses the natural format of the target. If @code{GNUTARGET} is set to @code{default} then BFD attempts to discover the input format by examining binary input files; this method often succeeds, but there are potential ambiguities, since @@ -2182,7 +2213,7 @@ Several linker script commands deal with files. @cindex including a linker script Include the linker script @var{filename} at this point. The file will be searched for in the current directory, and in any directory specified -with the @code{-L} option. You can nest calls to @code{INCLUDE} up to +with the @option{-L} option. You can nest calls to @code{INCLUDE} up to 10 levels deep. @item INPUT(@var{file}, @var{file}, @dots{}) @@ -2206,7 +2237,7 @@ it is not found, the linker will search through the archive library search path. See the description of @samp{-L} in @ref{Options,,Command Line Options}. -If you use @samp{INPUT (-l@var{file})}, @code{ld} will transform the +If you use @samp{INPUT (-l@var{file})}, @command{ld} will transform the name to @code{lib@var{file}.a}, as with the command line argument @samp{-l}. @@ -2241,7 +2272,7 @@ output file other than the usual default of @file{a.out}. @cindex archive search path in linker script @cindex search path in linker script The @code{SEARCH_DIR} command adds @var{path} to the list of paths where -@code{ld} looks for archive libraries. Using +@command{ld} looks for archive libraries. Using @code{SEARCH_DIR(@var{path})} is exactly like using @samp{-L @var{path}} on the command line (@pxref{Options,,Command Line Options}). If both are used, then the linker will search both paths. Paths specified using @@ -2269,7 +2300,7 @@ A couple of linker script commands deal with object file formats. @cindex output file format in linker script The @code{OUTPUT_FORMAT} command names the BFD format to use for the output file (@pxref{BFD}). Using @code{OUTPUT_FORMAT(@var{bfdname})} is -exactly like using @samp{-oformat @var{bfdname}} on the command line +exactly like using @samp{--oformat @var{bfdname}} on the command line (@pxref{Options,,Command Line Options}). If both are used, the command line option takes precedence. @@ -2329,7 +2360,7 @@ command has the same effect as the @samp{-u} command-line option. @kindex FORCE_COMMON_ALLOCATION @cindex common allocation in linker script This command has the same effect as the @samp{-d} command-line option: -to make @code{ld} assign space to common symbols even if a relocatable +to make @command{ld} assign space to common symbols even if a relocatable output file is specified (@samp{-r}). @item INHIBIT_COMMON_ALLOCATION @@ -2342,7 +2373,7 @@ to common symbols even for a non-relocatable output file. @item NOCROSSREFS(@var{section} @var{section} @dots{}) @kindex NOCROSSREFS(@var{sections}) @cindex cross references -This command may be used to tell @code{ld} to issue an error about any +This command may be used to tell @command{ld} to issue an error about any references among certain output sections. In certain types of programs, particularly on embedded systems when @@ -2352,7 +2383,7 @@ errors. For example, it would be an error if code in one section called a function defined in the other section. The @code{NOCROSSREFS} command takes a list of output section names. If -@code{ld} detects any cross references between the sections, it reports +@command{ld} detects any cross references between the sections, it reports an error and returns a non-zero exit status. Note that the @code{NOCROSSREFS} command uses output section names, not input section names. @@ -2922,7 +2953,7 @@ You may use the @code{FILL} command to set the fill pattern for the current section. It is followed by an expression in parentheses. Any otherwise unspecified regions of memory within the section (for example, gaps left due to the required alignment of input sections) are filled -with the four least significant bytes of the expression, repeated as +with the value of the expression, repeated as necessary. A @code{FILL} statement covers memory locations after the point at which it occurs in the section definition; by including more than one @code{FILL} statement, you can have different fill patterns in @@ -2935,10 +2966,11 @@ FILL(0x90909090) @end smallexample The @code{FILL} command is similar to the @samp{=@var{fillexp}} output -section attribute (@pxref{Output Section Fill}), but it only affects the +section attribute, but it only affects the part of the section following the @code{FILL} command, rather than the entire section. If both are used, the @code{FILL} command takes -precedence. +precedence. @xref{Output Section Fill}, for details on the fill +expression. @node Output Section Keywords @subsection Output section keywords @@ -3217,11 +3249,17 @@ You can set the fill pattern for an entire section by using @samp{=@var{fillexp}}. @var{fillexp} is an expression (@pxref{Expressions}). Any otherwise unspecified regions of memory within the output section (for example, gaps left due to the required -alignment of input sections) will be filled with the four least -significant bytes of the value, repeated as necessary. +alignment of input sections) will be filled with the value, repeated as +necessary. If the fill expression is a simple hex number, ie. a string +of hex digit starting with @samp{0x} and without a trailing @samp{k} or @samp{M}, then +an arbitrarily long sequence of hex digits can be used to specify the +fill pattern; Leading zeros become part of the pattern too. For all +other cases, including extra parentheses or a unary @code{+}, the fill +pattern is the four least significant bytes of the value of the +expression. In all cases, the number is big-endian. You can also change the fill value with a @code{FILL} command in the -output section commands; see @ref{Output Section Data}. +output section commands; (@pxref{Output Section Data}). Here is a simple example: @smallexample @@ -3664,7 +3702,10 @@ This example version script defines three version nodes. The first version node defined is @samp{VERS_1.1}; it has no other dependencies. The script binds the symbol @samp{foo1} to @samp{VERS_1.1}. It reduces a number of symbols to local scope so that they are not visible outside -of the shared library. +of the shared library; this is done using wildcard patterns, so that any +symbol whose name begins with @samp{old}, @samp{original}, or @samp{new} +is matched. The wildcard patterns available are the same as those used +in the shell when matching filenames (also known as ``globbing''). Next, the version script defines node @samp{VERS_1.2}. This node depends upon @samp{VERS_1.1}. The script binds the symbol @samp{foo2} @@ -3685,6 +3726,15 @@ they might suggest to the person reading them. The @samp{2.0} version could just as well have appeared in between @samp{1.1} and @samp{1.2}. However, this would be a confusing way to write a version script. +Node name can be omited, provided it is the only version node +in the version script. Such version script doesn't assign any versions to +symbols, only selects which symbols will be globally visible out and which +won't. + +@smallexample +@{ global: foo; bar; local: *; @} +@end smallexample + When you link an application against a shared library that has versioned symbols, the application itself knows which version of each symbol it requires, and it also knows which version nodes it needs from each @@ -3718,7 +3768,8 @@ __asm__(".symver original_foo,foo@@VERS_1.1"); in the C source file. This renames the function @samp{original_foo} to be an alias for @samp{foo} bound to the version node @samp{VERS_1.1}. The @samp{local:} directive can be used to prevent the symbol -@samp{original_foo} from being exported. +@samp{original_foo} from being exported. A @samp{.symver} directive +takes precedence over a version script. The second GNU extension is to allow multiple versions of the same function to appear in a given shared library. In this way you can make @@ -4107,12 +4158,7 @@ SECTIONS @{ @dots{} @cindex round up location counter @cindex align location counter Return the location counter (@code{.}) aligned to the next @var{exp} -boundary. @var{exp} must be an expression whose value is a power of -two. This is equivalent to -@smallexample -(. + @var{exp} - 1) & ~(@var{exp} - 1) -@end smallexample - +boundary. @code{ALIGN} doesn't change the value of the location counter---it just does arithmetic on it. Here is an example which aligns the output @code{.data} section to the next @code{0x2000} byte boundary after the @@ -4142,6 +4188,45 @@ This is a synonym for @code{ALIGN}, for compatibility with older linker scripts. It is most often seen when setting the address of an output section. +@item DATA_SEGMENT_ALIGN(@var{maxpagesize}, @var{commonpagesize}) +@kindex DATA_SEGMENT_ALIGN(@var{maxpagesize}, @var{commonpagesize}) +This is equivalent to either +@smallexample +(ALIGN(@var{maxpagesize}) + (. & (@var{maxpagesize} - 1))) +@end smallexample +or +@smallexample +(ALIGN(@var{maxpagesize}) + (. & (@var{maxpagesize} - @var{commonpagesize}))) +@end smallexample +@noindent +depending on whether the latter uses fewer @var{commonpagesize} sized pages +for the data segment (area between the result of this expression and +@code{DATA_SEGMENT_END}) than the former or not. +If the latter form is used, it means @var{commonpagesize} bytes of runtime +memory will be saved at the expense of up to @var{commonpagesize} wasted +bytes in the on-disk file. + +This expression can only be used directly in @code{SECTIONS} commands, not in +any output section descriptions and only once in the linker script. +@var{commonpagesize} should be less or equal to @var{maxpagesize} and should +be the system page size the object wants to be optimized for (while still +working on system page sizes up to @var{maxpagesize}). + +@noindent +Example: +@smallexample + . = DATA_SEGMENT_ALIGN(0x10000, 0x2000); +@end smallexample + +@item DATA_SEGMENT_END(@var{exp}) +@kindex DATA_SEGMENT_END(@var{exp}) +This defines the end of data segment for @code{DATA_SEGMENT_ALIGN} +evaluation purposes. + +@smallexample + . = DATA_SEGMENT_END(.); +@end smallexample + @item DEFINED(@var{symbol}) @kindex DEFINED(@var{symbol}) @cindex symbol defaults @@ -4255,8 +4340,8 @@ read. This can affect archive searching. @chapter Machine Dependent Features @cindex machine dependencies -@code{ld} has additional features on some platforms; the following -sections describe them. Machines where @code{ld} has no additional +@command{ld} has additional features on some platforms; the following +sections describe them. Machines where @command{ld} has no additional functionality are not listed. @menu @@ -4268,7 +4353,7 @@ functionality are not listed. * MMIX:: @code{ld} and MMIX @end ifset @ifset TICOFF -* TI COFF:: @code{ld} and TI COFF +* TI COFF:: @command{ld} and TI COFF @end ifset @end menu @end ifset @@ -4281,16 +4366,16 @@ functionality are not listed. @end ifclear @node H8/300 -@section @code{ld} and the H8/300 +@section @command{ld} and the H8/300 @cindex H8/300 support -For the H8/300, @code{ld} can perform these global optimizations when +For the H8/300, @command{ld} can perform these global optimizations when you specify the @samp{--relax} command-line option. @table @emph @cindex relaxing on H8/300 @item relaxing address modes -@code{ld} finds all @code{jsr} and @code{jmp} instructions whose +@command{ld} finds all @code{jsr} and @code{jmp} instructions whose targets are within eight bits, and turns them into eight-bit program-counter relative @code{bsr} and @code{bra} instructions, respectively. @@ -4298,7 +4383,7 @@ respectively. @cindex synthesizing on H8/300 @item synthesizing instructions @c FIXME: specifically mov.b, or any mov instructions really? -@code{ld} finds all @code{mov.b} instructions which use the +@command{ld} finds all @code{mov.b} instructions which use the sixteen-bit absolute address form, but refer to the top page of memory, and changes them to use the eight-bit address form. (That is: the linker turns @samp{mov.b @code{@@}@var{aa}:16} into @@ -4316,9 +4401,9 @@ top page of memory). @c This stuff is pointless to say unless you're especially concerned @c with Hitachi chips; don't enable it for generic case, please. @node Hitachi -@chapter @code{ld} and other Hitachi chips +@chapter @command{ld} and other Hitachi chips -@code{ld} also supports the H8/300H, the H8/500, and the Hitachi SH. No +@command{ld} also supports the H8/300H, the H8/500, and the Hitachi SH. No special features, commands, or command-line options are required for these chips. @end ifset @@ -4330,7 +4415,7 @@ these chips. @end ifclear @node i960 -@section @code{ld} and the Intel 960 family +@section @command{ld} and the Intel 960 family @cindex i960 support @@ -4342,7 +4427,7 @@ linker's search strategy for archive libraries, to support the use of libraries specific to each particular architecture, by including in the search loop names suffixed with the string identifying the architecture. -For example, if your @code{ld} command line included @w{@samp{-ACA}} as +For example, if your @command{ld} command line included @w{@samp{-ACA}} as well as @w{@samp{-ltry}}, the linker would look (in its built-in search paths, and in any paths you specify with @samp{-L}) for a library with the names @@ -4365,13 +4450,13 @@ the 960 architecture family allows combination of target architectures; each use will add another pair of name variants to search for when @w{@samp{-l}} specifies a library. -@cindex @code{--relax} on i960 +@cindex @option{--relax} on i960 @cindex relaxing on i960 -@code{ld} supports the @samp{--relax} option for the i960 family. If -you specify @samp{--relax}, @code{ld} finds all @code{balx} and +@command{ld} supports the @samp{--relax} option for the i960 family. If +you specify @samp{--relax}, @command{ld} finds all @code{balx} and @code{calx} instructions whose targets are within 24 bits, and turns them into 24-bit program-counter relative @code{bal} and @code{cal} -instructions, respectively. @code{ld} also turns @code{cal} +instructions, respectively. @command{ld} also turns @code{cal} instructions into @code{bal} instructions when it determines that the target subroutine is a leaf routine (that is, the target subroutine does not itself call any subroutines). @@ -4386,11 +4471,11 @@ not itself call any subroutines). @end ifclear @node ARM -@section @code{ld}'s support for interworking between ARM and Thumb code +@section @command{ld}'s support for interworking between ARM and Thumb code @cindex ARM interworking support @kindex --support-old-code -For the ARM, @code{ld} will generate code stubs to allow functions calls +For the ARM, @command{ld} will generate code stubs to allow functions calls betweem ARM and Thumb code. These stubs only work with code that has been compiled and assembled with the @samp{-mthumb-interwork} command line option. If it is necessary to link with old ARM object files or @@ -4411,18 +4496,18 @@ branched to using a BX instruction, and the program will start executing in Thumb mode straight away. @node HPPA ELF32 -@section @code{ld} and HPPA 32-bit ELF support +@section @command{ld} and HPPA 32-bit ELF support @cindex HPPA multiple sub-space stubs @kindex --multi-subspace -When generating a shared library, @code{ld} will by default generate +When generating a shared library, @command{ld} will by default generate import stubs suitable for use with a single sub-space application. -The @samp{--multi-subspace} switch causes @code{ld} to generate export +The @samp{--multi-subspace} switch causes @command{ld} to generate export stubs, and different (larger) import stubs suitable for use with multiple sub-spaces. @cindex HPPA stub grouping @kindex --stub-group-size=@var{N} -Long branch stubs and import/export stubs are placed by @code{ld} in +Long branch stubs and import/export stubs are placed by @command{ld} in stub sections located between groups of input sections. @samp{--stub-group-size} specifies the maximum size of a group of input sections handled by one stub section. Since branch offsets are signed, @@ -4433,7 +4518,7 @@ prediction) that stub sections only serve one group of input sections. A negative value for @samp{N} chooses this scheme, ensuring that branches to stubs always use a negative offset. Two special values of @samp{N} are recognized, @samp{1} and @samp{-1}. These both instruct -@code{ld} to automatically size input section groups for the branch types +@command{ld} to automatically size input section groups for the branch types detected, with the same behaviour regarding stub placement as other positive or negative values of @samp{N} respectively. @@ -4470,13 +4555,13 @@ are left out from an mmo file. @ifset TICOFF @node TI COFF -@section @code{ld}'s support for various TI COFF versions +@section @command{ld}'s support for various TI COFF versions @cindex TI COFF versions @kindex --format=@var{version} The @samp{--format} switch allows selection of one of the various TI COFF versions. The latest of this writing is 2; versions 0 and 1 are also supported. The TI COFF versions also vary in header byte-order -format; @code{ld} will read any version or byte order, but the output +format; @command{ld} will read any version or byte order, but the output header format depends on the default specified by the specific target. @end ifset @@ -4529,16 +4614,16 @@ conversion and during output. @xref{BFD information loss}. @node Reporting Bugs @chapter Reporting Bugs -@cindex bugs in @code{ld} -@cindex reporting bugs in @code{ld} +@cindex bugs in @command{ld} +@cindex reporting bugs in @command{ld} -Your bug reports play an essential role in making @code{ld} reliable. +Your bug reports play an essential role in making @command{ld} reliable. Reporting a bug may help you by bringing a solution to your problem, or it may not. But in any case the principal function of a bug report is -to help the entire community by making the next version of @code{ld} +to help the entire community by making the next version of @command{ld} work better. Bug reports are your contribution to the maintenance of -@code{ld}. +@command{ld}. In order for a bug report to serve its purpose, you must include the information that enables us to fix the bug. @@ -4560,37 +4645,37 @@ If you are not sure whether you have found a bug, here are some guidelines: @cindex crash of linker @item If the linker gets a fatal signal, for any input whatever, that is a -@code{ld} bug. Reliable linkers never crash. +@command{ld} bug. Reliable linkers never crash. @cindex error on valid input @item -If @code{ld} produces an error message for valid input, that is a bug. +If @command{ld} produces an error message for valid input, that is a bug. @cindex invalid input @item -If @code{ld} does not produce an error message for invalid input, that +If @command{ld} does not produce an error message for invalid input, that may be a bug. In the general case, the linker can not verify that object files are correct. @item If you are an experienced user of linkers, your suggestions for -improvement of @code{ld} are welcome in any case. +improvement of @command{ld} are welcome in any case. @end itemize @node Bug Reporting @section How to report bugs @cindex bug reports -@cindex @code{ld} bugs, reporting +@cindex @command{ld} bugs, reporting A number of companies and individuals offer support for @sc{gnu} -products. If you obtained @code{ld} from a support organization, we +products. If you obtained @command{ld} from a support organization, we recommend you contact that organization first. You can find contact information for many support companies and individuals in the file @file{etc/SERVICE} in the @sc{gnu} Emacs distribution. -Otherwise, send bug reports for @code{ld} to +Otherwise, send bug reports for @command{ld} to @samp{bug-binutils@@gnu.org}. The fundamental principle of reporting bugs usefully is this: @@ -4599,17 +4684,18 @@ fact or leave it out, state it! Often people omit facts because they think they know what causes the problem and assume that some details do not matter. Thus, you might -assume that the name of a symbol you use in an example does not matter. -Well, probably it does not, but one cannot be sure. Perhaps the bug is -a stray memory reference which happens to fetch from the location where -that name is stored in memory; perhaps, if the name were different, the -contents of that location would fool the linker into doing the right -thing despite the bug. Play it safe and give a specific, complete -example. That is the easiest thing for you to do, and the most helpful. - -Keep in mind that the purpose of a bug report is to enable us to fix the bug if -it is new to us. Therefore, always write your bug reports on the assumption -that the bug has not been reported previously. +assume that the name of a symbol you use in an example does not +matter. Well, probably it does not, but one cannot be sure. Perhaps +the bug is a stray memory reference which happens to fetch from the +location where that name is stored in memory; perhaps, if the name +were different, the contents of that location would fool the linker +into doing the right thing despite the bug. Play it safe and give a +specific, complete example. That is the easiest thing for you to do, +and the most helpful. + +Keep in mind that the purpose of a bug report is to enable us to fix +the bug if it is new to us. Therefore, always write your bug reports +on the assumption that the bug has not been reported previously. Sometimes people give a few sketchy facts and ask, ``Does this ring a bell?'' Those bug reports are useless, and we urge everyone to @@ -4620,14 +4706,14 @@ To enable us to fix the bug, you should include all these things: @itemize @bullet @item -The version of @code{ld}. @code{ld} announces it if you start it with +The version of @command{ld}. @command{ld} announces it if you start it with the @samp{--version} argument. Without this, we will not know whether there is any point in looking for -the bug in the current version of @code{ld}. +the bug in the current version of @command{ld}. @item -Any patches you may have applied to the @code{ld} source, including any +Any patches you may have applied to the @command{ld} source, including any patches made to the @code{BFD} library. @item @@ -4635,7 +4721,7 @@ The type of machine you are using, and the operating system name and version number. @item -What compiler (and its version) was used to compile @code{ld}---e.g. +What compiler (and its version) was used to compile @command{ld}---e.g. ``@code{gcc-2.7}''. @item @@ -4649,10 +4735,13 @@ and then we might not encounter the bug. @item A complete input file, or set of input files, that will reproduce the -bug. It is generally most helpful to send the actual object files, -uuencoded if necessary to get them through the mail system. Making them -available for anonymous FTP is not as good, but may be the only -reasonable choice for large object files. +bug. It is generally most helpful to send the actual object files +provided that they are reasonably small. Say no more than 10K. For +bigger files you can either make them available by FTP or HTTP or else +state that you are willing to send the object file(s) to whomever +requests them. (Note - your email will be going to a mailing list, so +we do not want to clog it up with large attachments). But small +attachments are best. If the source files were assembled using @code{gas} or compiled using @code{gcc}, then it may be OK to send the source files rather than the @@ -4664,14 +4753,14 @@ how @code{gas} or @code{gcc} were configured. A description of what behavior you observe that you believe is incorrect. For example, ``It gets a fatal signal.'' -Of course, if the bug is that @code{ld} gets a fatal signal, then we +Of course, if the bug is that @command{ld} gets a fatal signal, then we will certainly notice it. But if the bug is incorrect output, we might not notice unless it is glaringly wrong. You might as well not give us a chance to make a mistake. Even if the problem you experience is a fatal signal, you should still say so explicitly. Suppose something strange is going on, such as, your -copy of @code{ld} is out of synch, or you have encountered a bug in the +copy of @command{ld} is out of synch, or you have encountered a bug in the C library on your system. (This has happened!) Your copy might crash and ours would not. If you told us to expect a crash, then when ours fails to crash, we would know that the bug was not happening for us. If @@ -4679,10 +4768,10 @@ you had not told us to expect a crash, then we would not be able to draw any conclusion from our observations. @item -If you wish to suggest changes to the @code{ld} source, send us context +If you wish to suggest changes to the @command{ld} source, send us context diffs, as generated by @code{diff} with the @samp{-u}, @samp{-c}, or @samp{-p} option. Always send diffs from the old file to the new file. -If you even discuss something in the @code{ld} source, refer to it by +If you even discuss something in the @command{ld} source, refer to it by context, not by line number. The line numbers in our development sources will not match those in your @@ -4720,7 +4809,7 @@ the necessary information, such as the test case, on the assumption that a patch is all we need. We might see problems with your patch and decide to fix the problem another way, or we might not understand it at all. -Sometimes with a program as complicated as @code{ld} it is very hard to +Sometimes with a program as complicated as @command{ld} it is very hard to construct an example that will make the program follow a certain path through the code. If you do not send us the example, we will not be able to construct one, so we will not be able to verify that the bug is @@ -4740,12 +4829,12 @@ things without first using the debugger to find the facts. @node MRI @appendix MRI Compatible Script Files @cindex MRI compatibility -To aid users making the transition to @sc{gnu} @code{ld} from the MRI -linker, @code{ld} can use MRI compatible linker scripts as an +To aid users making the transition to @sc{gnu} @command{ld} from the MRI +linker, @command{ld} can use MRI compatible linker scripts as an alternative to the more general-purpose linker scripting language described in @ref{Scripts}. MRI compatible linker scripts have a much simpler command set than the scripting language otherwise used with -@code{ld}. @sc{gnu} @code{ld} supports the most commonly used MRI +@command{ld}. @sc{gnu} @command{ld} supports the most commonly used MRI linker commands; these commands are described here. In general, MRI scripts aren't of much use with the @code{a.out} object @@ -4758,7 +4847,7 @@ You can specify a file containing an MRI-compatible script using the Each command in an MRI-compatible script occupies its own line; each command line starts with the keyword that identifies the command (though blank lines are also allowed for punctuation). If a line of an -MRI-compatible script begins with an unrecognized keyword, @code{ld} +MRI-compatible script begins with an unrecognized keyword, @command{ld} issues a warning message, but continues processing the script. Lines beginning with @samp{*} are comments. @@ -4771,7 +4860,7 @@ The following list shows only the upper-case form of each command. @cindex @code{ABSOLUTE} (MRI) @item ABSOLUTE @var{secname} @itemx ABSOLUTE @var{secname}, @var{secname}, @dots{} @var{secname} -Normally, @code{ld} includes in the output file all sections from all +Normally, @command{ld} includes in the output file all sections from all the input files. However, in an MRI-compatible script, you can use the @code{ABSOLUTE} command to restrict the sections that will be present in your output program. If the @code{ABSOLUTE} command is used at all in a @@ -4826,7 +4915,7 @@ COFF (the @samp{coff-m68k} variant in BFD), if @var{output-format} is @cindex @code{LIST} (MRI) @item LIST @var{anything}@dots{} Print (to the standard output file) a link map, as produced by the -@code{ld} command-line option @samp{-M}. +@command{ld} command-line option @samp{-M}. The keyword @code{LIST} may be followed by anything on the same line, with no change in its effect. @@ -4835,19 +4924,19 @@ same line, with no change in its effect. @item LOAD @var{filename} @itemx LOAD @var{filename}, @var{filename}, @dots{} @var{filename} Include one or more object file @var{filename} in the link; this has the -same effect as specifying @var{filename} directly on the @code{ld} +same effect as specifying @var{filename} directly on the @command{ld} command line. @cindex @code{NAME} (MRI) @item NAME @var{output-name} -@var{output-name} is the name for the program produced by @code{ld}; the +@var{output-name} is the name for the program produced by @command{ld}; the MRI-compatible command @code{NAME} is equivalent to the command-line option @samp{-o} or the general script language command @code{OUTPUT}. @cindex @code{ORDER} (MRI) @item ORDER @var{secname}, @var{secname}, @dots{} @var{secname} @itemx ORDER @var{secname} @var{secname} @var{secname} -Normally, @code{ld} orders the sections in its output file in the +Normally, @command{ld} orders the sections in its output file in the order in which they first appear in the input files. In an MRI-compatible script, you can override this ordering with the @code{ORDER} command. The sections you list with @code{ORDER} will appear first in your output