binutils-gdb/ld/scripttempl/elfmicroblaze.sc
Alan Modra 2edab91c10 Make assignments to dot keep an empty output section.
An assignment to dot in an output section that allocates space of
course keeps the output section.  Here, I'm changing the behaviour for
assignments that don't allocate space.  The idea is not so much to
allow people to force output of an empty section with ". = .", but
to fix cases where an otherwise empty section has padding added by an
alignment expression that changes with relaxation or .eh_frame
editing.  Such a section might have zero size before relaxation and so
be stripped incorrectly.

ld/
	* ld.texinfo (Output Section Discarding): Mention assigning to dot
	as a way of keeping otherwise empty sections.
	* ldexp.c (is_dot, is_value, is_sym_value, is_dot_ne_0,
	is_dot_plus_0, is_align_conditional): New predicates.
	(exp_fold_tree_1): Set SEC_KEEP when assigning to dot inside an
	output section, except for some special cases.
	* scripttempl/elfmicroblaze.sc: Use canonical form to align at
	end of .heap and .stack.
ld/testsuite/
	* ld-shared/elf-offset.ld: Align end of .bss with canonical form
	of ALIGN that allows an empty .bss to be removed.
	* ld-arm/arm-dyn.ld: Likewise.
	* ld-arm/arm-lib.ld: Likewise.
	* ld-elfvsb/elf-offset.ld: Likewise.
	* ld-mips-elf/mips-dyn.ld: Likewise.
	* ld-mips-elf/mips-lib.ld: Likewise.
	* ld-arm/arm-no-rel-plt.ld: Remove duplicate ALIGN.
	* ld-powerpc/vle-multiseg-1.ld: Remove ALIGN at start of section.
	ALIGN address of section instead.
	* ld-powerpc/vle-multiseg-2.ld: Likewise.
	* ld-powerpc/vle-multiseg-3.ld: Likewise.
	* ld-powerpc/vle-multiseg-4.ld: Likewise.
	* ld-powerpc/vle-multiseg-6.ld: Likewise.
	* ld-scripts/empty-aligned.d: Check section headers not program
	headers.  Remove xfail and notarget.
	* ld-scripts/empty-aligned.t: Use canonical ALIGN for end of .text2.
2014-01-22 11:58:29 +10:30

223 lines
5.9 KiB
Scala

# Adapted from mips.sc
# These variables may be overridden by the emulation file. The
# defaults are appropriate for a DECstation running Ultrix.
test -z "$ENTRY" && ENTRY=_start
#test -z "$TEXT_START_ADDR" && TEXT_START_ADDR="0x0"
CTOR=".ctors ${CONSTRUCTING-0} :
{
${CONSTRUCTING+${CTOR_START}}
/* gcc uses crtbegin.o to find the start of
the constructors, so we make sure it is
first. Because this is a wildcard, it
doesn't matter if the user does not
actually link against crtbegin.o; the
linker won't look for a file to match a
wildcard. The wildcard also means that it
doesn't matter which directory crtbegin.o
is in. */
KEEP (*crtbegin.o(.ctors))
/* We don't want to include the .ctor section from
from the crtend.o file until after the sorted ctors.
The .ctor section from the crtend file contains the
end of ctors marker and it must be last */
KEEP (*(EXCLUDE_FILE (*crtend.o) .ctors))
KEEP (*(SORT(.ctors.*)))
KEEP (*(.ctors))
${CONSTRUCTING+${CTOR_END}}
}"
DTOR=" .dtors ${CONSTRUCTING-0} :
{
${CONSTRUCTING+${DTOR_START}}
KEEP (*crtbegin.o(.dtors))
KEEP (*(EXCLUDE_FILE (*crtend.o) .dtors))
KEEP (*(SORT(.dtors.*)))
KEEP (*(.dtors))
${CONSTRUCTING+${DTOR_END}}
}"
cat <<EOF
OUTPUT_FORMAT("${OUTPUT_FORMAT}", "${BIG_OUTPUT_FORMAT}",
"${LITTLE_OUTPUT_FORMAT}")
/*${LIB_SEARCH_DIRS}*/
${RELOCATING+${LIB_SEARCH_DIRS}}
${RELOCATING+ENTRY (${ENTRY})}
_TEXT_START_ADDR = DEFINED(_TEXT_START_ADDR) ? _TEXT_START_ADDR : 0x50;
_HEAP_SIZE = DEFINED(_HEAP_SIZE) ? _HEAP_SIZE : 0x0;
_STACK_SIZE = DEFINED(_STACK_SIZE) ? _STACK_SIZE : 0x400;
SECTIONS
{
.vectors.reset 0x0 : { KEEP (*(.vectors.reset)) } = 0
.vectors.sw_exception 0x8 : { KEEP (*(.vectors.sw_exception)) } = 0
.vectors.interrupt 0x10 : { KEEP (*(.vectors.interrupt)) } = 0
.vectors.debug_sw_break 0x18 : { KEEP (*(.vectors.debug_sw_break)) } = 0
.vectors.hw_exception 0x20 : { KEEP (*(.vectors.hw_exception)) } = 0
${RELOCATING+. = _TEXT_START_ADDR;}
${RELOCATING+ _ftext = .;}
.text : {
${RELOCATING+*(.text)}
${RELOCATING+*(.text.*)}
${RELOCATING+*(.gnu.linkonce.t.*)}
}
${RELOCATING+ _etext = .;}
.init : { KEEP (*(.init)) } =0
.fini : { KEEP (*(.fini)) } =0
${RELOCATING+PROVIDE (__CTOR_LIST__ = .);}
${RELOCATING+PROVIDE (___CTOR_LIST__ = .);}
${RELOCATING+${CTOR}}
${RELOCATING+PROVIDE (__CTOR_END__ = .);}
${RELOCATING+PROVIDE (___CTOR_END__ = .);}
${RELOCATING+PROVIDE (__DTOR_LIST__ = .);}
${RELOCATING+PROVIDE (___DTOR_LIST__ = .);}
${RELOCATING+${DTOR}}
${RELOCATING+PROVIDE (__DTOR_END__ = .);}
${RELOCATING+PROVIDE (___DTOR_END__ = .);}
${RELOCATING+ . = ALIGN(4);}
${RELOCATING+ _frodata = . ;}
.rodata : {
${RELOCATING+*(.rodata)}
${RELOCATING+*(.rodata.*)}
${RELOCATING+*(.gnu.linkonce.r.*)}
${CONSTRUCTING+CONSTRUCTORS}; /* Is this needed? */
}
${RELOCATING+ _erodata = .;}
/* Alignments by 8 to ensure that _SDA2_BASE_ on a word boundary */
/* Note that .sdata2 and .sbss2 must be contiguous */
${RELOCATING+. = ALIGN(8);}
${RELOCATING+ _ssrw = .;}
.sdata2 : {
${RELOCATING+*(.sdata2)}
${RELOCATING+*(.sdata2.*)}
${RELOCATING+*(.gnu.linkonce.s2.*)}
}
${RELOCATING+. = ALIGN(4);}
.sbss2 : {
${RELOCATING+PROVIDE (__sbss2_start = .);}
${RELOCATING+*(.sbss2)}
${RELOCATING+*(.sbss2.*)}
${RELOCATING+*(.gnu.linkonce.sb2.*)}
${RELOCATING+PROVIDE (__sbss2_end = .);}
}
${RELOCATING+. = ALIGN(8);}
${RELOCATING+ _essrw = .;}
${RELOCATING+ _ssrw_size = _essrw - _ssrw;}
${RELOCATING+ PROVIDE (_SDA2_BASE_ = _ssrw + (_ssrw_size / 2 ));}
${RELOCATING+ . = ALIGN(4);}
${RELOCATING+ _fdata = .;}
.data : {
${RELOCATING+*(.data)}
${RELOCATING+*(.gnu.linkonce.d.*)}
${CONSTRUCTING+CONSTRUCTORS}; /* Is this needed? */
}
${RELOCATING+ _edata = . ;}
/* Added to handle pic code */
.got : {
${RELOCATING+*(.got)}
}
.got1 : {
${RELOCATING+*(.got1)}
}
.got2 : {
${RELOCATING+*(.got2)}
}
/* Added by Sathya to handle C++ exceptions */
.eh_frame : {
${RELOCATING+*(.eh_frame)}
}
.jcr : {
${RELOCATING+*(.jcr)}
}
.gcc_except_table : {
${RELOCATING+*(.gcc_except_table)}
}
/* Alignments by 8 to ensure that _SDA_BASE_ on a word boundary */
/* Note that .sdata and .sbss must be contiguous */
${RELOCATING+. = ALIGN(8);}
${RELOCATING+ _ssro = .;}
.sdata : {
${RELOCATING+*(.sdata)}
${RELOCATING+*(.sdata.*)}
${RELOCATING+*(.gnu.linkonce.s.*)}
}
${RELOCATING+. = ALIGN(4);}
.sbss : {
${RELOCATING+PROVIDE (__sbss_start = .);}
${RELOCATING+*(.sbss)}
${RELOCATING+*(.sbss.*)}
${RELOCATING+*(.gnu.linkonce.sb.*)}
${RELOCATING+PROVIDE (__sbss_end = .);}
}
${RELOCATING+. = ALIGN(8);}
${RELOCATING+ _essro = .;}
${RELOCATING+ _ssro_size = _essro - _ssro;}
${RELOCATING+PROVIDE (_SDA_BASE_ = _ssro + (_ssro_size / 2 ));}
${RELOCATING+ . = ALIGN(4);}
${RELOCATING+ _fbss = .;}
.bss : {
${RELOCATING+PROVIDE (__bss_start = .);}
${RELOCATING+*(.bss)}
${RELOCATING+*(.bss.*)}
${RELOCATING+*(.gnu.linkonce.b.*)}
${RELOCATING+*(COMMON)}
${RELOCATING+. = ALIGN(. != 0 ? 4 : 1);}
${RELOCATING+PROVIDE (__bss_end = .);}
}
${RELOCATING+ . = ALIGN(4);}
.heap : {
${RELOCATING+ _heap = .;}
${RELOCATING+ _heap_start = .;}
${RELOCATING+ . += _HEAP_SIZE;}
${RELOCATING+ _heap_end = .;}
}
${RELOCATING+ . = ALIGN(4);}
.stack : {
${RELOCATING+ _stack_end = .;}
${RELOCATING+ . += _STACK_SIZE;}
${RELOCATING+ . = ALIGN(. != 0 ? 8 : 1);}
${RELOCATING+ _stack = .;}
${RELOCATING+ _end = .;}
}
.tdata : {
${RELOCATING+*(.tdata)}
${RELOCATING+*(.tdata.*)}
${RELOCATING+*(.gnu.linkonce.td.*)}
}
.tbss : {
${RELOCATING+*(.tbss)}
${RELOCATING+*(.tbss.*)}
${RELOCATING+*(.gnu.linkonce.tb.*)}
}
}
EOF