diff options
Diffstat (limited to 'ld/ld.texinfo')
| -rw-r--r-- | ld/ld.texinfo | 181 |
1 files changed, 86 insertions, 95 deletions
diff --git a/ld/ld.texinfo b/ld/ld.texinfo index d6af574..290c3a0 100644 --- a/ld/ld.texinfo +++ b/ld/ld.texinfo @@ -1116,18 +1116,50 @@ for Solaris compatibility. The recognized keywords are: @table @samp +@item bndplt +Always generate BND prefix in PLT entries. Supported for Linux/x86_64. + +@item call-nop=prefix-addr +@itemx call-nop=suffix-nop +@itemx call-nop=prefix-@var{byte} +@itemx call-nop=suffix-@var{byte} +Specify the 1-byte @code{NOP} padding when transforming indirect call +to a locally defined function, foo, via its GOT slot. +@option{call-nop=prefix-addr} generates @code{0x67 call foo}. +@option{call-nop=suffix-nop} generates @code{call foo 0x90}. +@option{call-nop=prefix-@var{byte}} generates @code{@var{byte} call foo}. +@option{call-nop=suffix-@var{byte}} generates @code{call foo @var{byte}}. +Supported for i386 and x86_64. + @item combreloc -Combines multiple reloc sections and sorts them to make dynamic symbol -lookup caching possible. +@itemx nocombreloc +Combine multiple dynamic relocation sections and sort to improve +dynamic symbol lookup caching. Do not do this if @samp{nocombreloc}. @item common -Generate common symbols with the STT_COMMON type druing a relocatable -link. +@itemx nocommon +Generate common symbols with STT_COMMON type during a relocatable +link. Use STT_OBJECT type if @samp{nocommon}. + +@item common-page-size=@var{value} +Set the page size most commonly used to @var{value}. Memory image +layout will be optimized to minimize memory pages if the system is +using pages of this size. @item defs Disallows undefined symbols in object files. Undefined symbols in shared libraries are still allowed. +@item dynamic-undefined-weak +@itemx nodynamic-undefined-weak +Make undefined weak symbols dynamic when building a dynamic object, +if they are referenced from a regular object file and not forced local +by symbol visibility or versioning. Do not make them dynamic if +@samp{nodynamic-undefined-weak}. If neither option is given, a target +may default to either option being in force, or make some other +selection of undefined weak symbols dynamic. Not all targets support +these options. + @item execstack Marks the object as requiring executable stack. @@ -1144,6 +1176,15 @@ tag. Global auditing requires that any auditing library defined via the @option{--depaudit} or @option{-P} command line options be run for all dynamic objects loaded by the application. +@item ibtplt +Generate Intel Indirect Branch Tracking (IBT) enabled PLT entries. +Supported for Linux/i386 and Linux/x86_64. + +@item IBT +Generate GNU_PROPERTY_X86_FEATURE_1_IBT in .note.gnu.property section +to indicate compatibility with IBT. This also implies @option{ibtplt}. +Supported for Linux/i386 and Linux/x86_64. + @item initfirst This option is only meaningful when building a shared object. It marks the object so that its runtime initialization will occur @@ -1153,8 +1194,9 @@ the object will occur after the runtime finalization of any other objects. @item interpose -Marks the object that its symbol table interposes before all symbols -but the primary executable. +Specify that the dynamic loader should modify its symbol search order +so that symbols in this shared library interpose all other shared +libraries not so marked. @item lazy When generating an executable or shared library, mark it to tell the @@ -1163,132 +1205,81 @@ the function is called (lazy binding), rather than at load time. Lazy binding is the default. @item loadfltr -Marks the object that its filters be processed immediately at -runtime. +Specify that the object's filters be processed immediately at runtime. -@item muldefs -Allows multiple definitions. - -@item nocombreloc -Disables multiple reloc sections combining. +@item max-page-size=@var{value} +Set the maximum memory page size supported to @var{value}. -@item nocommon -Generate common symbols with the STT_OBJECT type druing a relocatable -link. +@item muldefs +Allow multiple definitions. @item nocopyreloc Disable linker generated .dynbss variables used in place of variables defined in shared libraries. May result in dynamic text relocations. @item nodefaultlib -Marks the object that the search for dependencies of this object will -ignore any default library search paths. +Specify that the dynamic loader search for dependencies of this object +should ignore any default library search paths. @item nodelete -Marks the object shouldn't be unloaded at runtime. +Specify that the object shouldn't be unloaded at runtime. @item nodlopen -Marks the object not available to @code{dlopen}. +Specify that the object is not available to @code{dlopen}. @item nodump -Marks the object can not be dumped by @code{dldump}. +Specify that the object can not be dumped by @code{dldump}. @item noexecstack Marks the object as not requiring executable stack. -@item text -Treat DT_TEXTREL in shared object as error. - -@item notext -Don't treat DT_TEXTREL in shared object as error. - -@item textoff -Don't treat DT_TEXTREL in shared object as error. +@item noextern-protected-data +Don't treat protected data symbols as external when building a shared +library. This option overrides the linker backend default. It can be +used to work around incorrect relocations against protected data symbols +generated by compiler. Updates on protected data symbols by another +module aren't visible to the resulting shared library. Supported for +i386 and x86-64. -@item norelro -Don't create an ELF @code{PT_GNU_RELRO} segment header in the object. +@item noreloc-overflow +Disable relocation overflow check. This can be used to disable +relocation overflow check if there will be no dynamic relocation +overflow at run-time. Supported for x86_64. @item now When generating an executable or shared library, mark it to tell the dynamic linker to resolve all symbols when the program is started, or -when the shared library is linked to using dlopen, instead of -deferring function call resolution to the point when the function is -first called. +when the shared library is loaded by dlopen, instead of deferring +function call resolution to the point when the function is first +called. @item origin -Marks the object may contain $ORIGIN. +Specify that the object requires @samp{$ORIGIN} handling in paths. @item relro +@itemx norelro Create an ELF @code{PT_GNU_RELRO} segment header in the object. This specifies a memory segment that should be made read-only after relocation, if supported. Specifying @samp{common-page-size} smaller than the system page size will render this protection ineffective. +Don't create an ELF @code{PT_GNU_RELRO} segment if @samp{norelro}. -@item max-page-size=@var{value} -Set the emulation maximum page size to @var{value}. - -@item common-page-size=@var{value} -Set the emulation common page size to @var{value}. +@item shstk +Generate GNU_PROPERTY_X86_FEATURE_1_SHSTK in .note.gnu.property section +to indicate compatibility with Intel Shadow Stack. Supported for +Linux/i386 and Linux/x86_64. @item stack-size=@var{value} -Specify a stack size for in an ELF @code{PT_GNU_STACK} segment. +Specify a stack size for an ELF @code{PT_GNU_STACK} segment. Specifying zero will override any default non-zero sized @code{PT_GNU_STACK} segment creation. -@item bndplt -Always generate BND prefix in PLT entries. Supported for Linux/x86_64. - -@item noextern-protected-data -Don't treat protected data symbol as external when building shared -library. This option overrides linker backend default. It can be used -to workaround incorrect relocations against protected data symbols -generated by compiler. Updates on protected data symbols by another -module aren't visible to the resulting shared library. Supported for -i386 and x86-64. - -@item dynamic-undefined-weak -Make undefined weak symbols dynamic when building a dynamic object, -if they are referenced from a regular object file and not forced local -by symbol visibility or versioning. Not all targets support this -option. - -@item nodynamic-undefined-weak -Do not make undefined weak symbols dynamic when building a dynamic -object. Not all targets support this option. If neither -@option{-z nodynamic-undefined-weak} nor @option{-z dynamic-undefined-weak} -are given, a target may default to either option being in force, or -make some other selection of undefined weak symbols dynamic. - -@item noreloc-overflow -Disable relocation overflow check. This can be used to disable -relocation overflow check if there will be no dynamic relocation -overflow at run-time. Supported for x86_64. - -@item call-nop=prefix-addr -@itemx call-nop=suffix-nop -@itemx call-nop=prefix-@var{byte} -@itemx call-nop=suffix-@var{byte} -Specify the 1-byte @code{NOP} padding when transforming indirect call -to a locally defined function, foo, via its GOT slot. -@option{call-nop=prefix-addr} generates @code{0x67 call foo}. -@option{call-nop=suffix-nop} generates @code{call foo 0x90}. -@option{call-nop=prefix-@var{byte}} generates @code{@var{byte} call foo}. -@option{call-nop=suffix-@var{byte}} generates @code{call foo @var{byte}}. -Supported for i386 and x86_64. - -@item ibtplt -Generate Intel Indirect Branch Tracking (IBT) enabled PLT entries. -Supported for Linux/i386 and Linux/x86_64. - -@item IBT -Generate GNU_PROPERTY_X86_FEATURE_1_IBT in .note.gnu.property section -to indicate compatibility with IBT. This also implies @option{ibtplt}. -Supported for Linux/i386 and Linux/x86_64. - -@item shstk -Generate GNU_PROPERTY_X86_FEATURE_1_SHSTK in .note.gnu.property section -to indicate compatibility with Intel Shadow Stack. Supported for -Linux/i386 and Linux/x86_64. +@item text +@itemx notext +@itemx textoff +Report an error if DT_TEXTREL is set, i.e., if the binary has dynamic +relocations in read-only sections. Don't report an error if +@samp{notext} or @samp{textoff}. @end table |