dynamic object, then you will probably need to use this option when
linking the program itself.
-You can also use the version script to control what symbols should
+You can also use the dynamic list to control what symbols should
be added to the dynamic symbol table if the output format supports it.
-See the description of @samp{--version-script} in @ref{VERSION}.
+See the description of @samp{--dynamic-list}.
@ifclear SingleFormat
@cindex big-endian objects
@kindex -X
@kindex --discard-locals
@cindex local symbols, deleting
-@cindex L, deleting symbols beginning
@item -X
@itemx --discard-locals
-Delete all temporary local symbols. For most targets, this is all local
-symbols whose names begin with @samp{L}.
+Delete all temporary local symbols. (These symbols start with
+system-specific local label prefixes, typically @samp{.L} for ELF systems
+or @samp{L} for traditional a.out systems.)
@kindex -y @var{symbol}
@kindex --trace-symbol=@var{symbol}
within the shared library. This option is only meaningful on ELF
platforms which support shared libraries.
+@kindex --dynamic-list=@var{dynamic-list-file}
+@item --dynamic-list=@var{dynamic-list-file}
+Specify the name of a dynamic list file to the linker. This is
+typically used when creating shared libraries to specify a list of
+global symbols whose references shouldn't be bound to the definition
+within the shared library, or creating dynamically linked executables
+to specify a list of symbols which should be added to the symbol table
+in the executable. This option is only meaningful on ELF platforms
+which support shared libraries.
+
+The format of the dynamic list is the same as the version node without
+scope and node name. See @ref{VERSION} for more information.
+
+@kindex --dynamic-list-cpp-typeinfo
+@item --dynamic-list-cpp-typeinfo
+Provide the builtin dynamic list for C++ runtime type identification.
+
@kindex --check-sections
@kindex --no-check-sections
@item --check-sections
@itemx --no-gc-sections
Enable garbage collection of unused input sections. It is ignored on
targets that do not support this option. This option is not compatible
-with @samp{-r}. The default behaviour (of not performing this garbage
-collection) can be restored by specifying @samp{--no-gc-sections} on
-the command line.
+with @samp{-r} or @samp{--emit-relocs}. The default behaviour (of not
+performing this garbage collection) can be restored by specifying
+@samp{--no-gc-sections} on the command line.
@kindex --print-gc-sections
@kindex --no-print-gc-sections
@cindex discarding sections
@cindex sections, discarding
@cindex removing sections
-The linker will not create output section which do not have any
-contents. This is for convenience when referring to input sections that
-may or may not be present in any of the input files. For example:
+The linker will not create output sections with no contents. This is
+for convenience when referring to input sections that may or may not
+be present in any of the input files. For example:
@smallexample
-.foo @{ *(.foo) @}
+.foo : @{ *(.foo) @}
@end smallexample
@noindent
will only create a @samp{.foo} section in the output file if there is a
-@samp{.foo} section in at least one input file.
+@samp{.foo} section in at least one input file, and if the input
+sections are not all empty. Other link script directives that allocate
+space in an output section will also create the output section.
-If you use anything other than an input section description as an output
-section command, such as a symbol assignment, then the output section
-will always be created, even if there are no matching input sections.
+The linker will ignore address assignments (@xref{Output Section Address})
+on discarded output sections, except when the linker script defines
+symbols in the output section. In that case the linker will obey
+the address assignments, possibly advancing dot and/or current lma
+even though the section is discarded.
@cindex /DISCARD/
The special output section name @samp{/DISCARD/} may be used to discard
an output section description sets the VMA (@pxref{Output Section
Address}).
-The linker will normally set the LMA equal to the VMA. You can change
-that by using the @code{AT} keyword. The expression @var{lma} that
-follows the @code{AT} keyword specifies the load address of the
-section.
+The expression @var{lma} that follows the @code{AT} keyword specifies
+the load address of the section.
Alternatively, with @samp{AT>@var{lma_region}} expression, you may
specify a memory region for the section's load address. @xref{MEMORY}.
Note that if the section has not had a VMA assigned to it then the
linker will use the @var{lma_region} as the VMA region as well.
+
+If neither @code{AT} nor @code{AT>} is specified for an allocatable
+section, the linker will set the LMA such that the difference between
+VMA and LMA for the section is the same as the preceding output
+section in the same region. If there is no preceding output section
+or the section is not allocatable, the linker will set the LMA equal
+to the VMA.
@xref{Output Section Region}.
@cindex ROM initialized data
@cindex holes
Assigning a value to @code{.} will cause the location counter to be
moved. This may be used to create holes in the output section. The
-location counter may never be moved backwards.
+location counter may not be moved backwards inside an output section,
+and may not be moved backwards outside of an output section if so
+doing creates areas with overlapping LMAs.
@smallexample
SECTIONS
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