A global or extern definition can now contain the keyword "weak" (or
"strong", although that is the default) to create a weak symbol or a
weak external reference, respectively.
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
note, preinit_array, init_array, and fini_array are ELF section types
that can matter to the assembly programmer.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Dead code elimination in ELF uses separate ELF sections for every
functions or data items that may be garbage collected. This can end up
being more than 32,633 sections which, when the ELF internal and
relocation sections are added in, can exceed the legacy ELF maximum of
65,279 sections.
Newer versions of the ELF specification has added support for much
larger number of sections by putting a place holder value (usually
SHN_XINDEX == 0xffff, but 0 in some cases) into fields where the
section index is a 16-bit value, and storing the full value in a
diffent place: the program header uses entries in section header 0,
the symbol table uses an auxiliary segment with the additional
indicies; the section header did not need it as the sh_link field is
already 32 (or 64) bits long.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Use a hash table to look up sections by name, and an RAA to look up
sections by index; thus remove O(n) searches. This becomes important
since ELF uses sections for dead code elimination.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Add support for the "merge" attribute in ELF, along with the
associated "strings" and size specifier attributes.
Fix a few places where we used "int", but a larger type really ought
to have been used.
Be a bit more lax about respecifying attributes. For example, align=
can be respecified; the highest resulting value is used.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
With buffered warnings, most warnings *must* be issued on every pass,
so ERR_PASS1 is simply wrong in most cases.
ERR_PASS1 now means "force this warning to be output even in
pass_first(). This is to be used for the case where the warning is
only executed in pass_first() code; this is highly discouraged as it
means the warnings will not appear in the list file and subsequent
passes may make the warning suddenly vanish.
ERR_PASS2 just as before suppresses an error or warning unless we are
in pass_final().
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
The directives code is already trying to do a bit more unified error
handling, so give ourselves a bit richer interface. At this point,
the conversion was pretty automatic so we probably return DIRR_OK
instead of DIRR_ERROR in a fair number of places, but that's okay.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Make the source code easier to understand and keep track of by
organizing it into subdirectories depending on the function.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
All Elf formats we're supporting at the moment have
are using same structures, move them into a header
and name then with elf_ prefix.
This makes a few fields to carry 64 bit integers while
in former Elf32|x formats they can be 32 bit wide, but
I think it's acceptable tradeoff.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Instead of implicit declaration of global symbols obtained
by STB_GLOBAL << 4, and local symbols by STB_LOCAL << 4
use ELF32_ST_MKBIND helpers.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Also made Makefile.in to handle dependency.
There are some makefiles in Mkfiles\ should
be fixed as well.
Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Add new copyright headers to the new output modules. As far as I
know, the only module which we still don't have a green light to
release under 2-BSD is outmacho.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Bump GLOBAL_TEMP_BASE so far that it *cannot* conflict for ELF32
(which has 24-bit symbol table indicies) and is *unlikely* to conflict
for ELF64 (which has 32-bit symbol table indicies.)
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Eliminiate hard-coded section numbers, at least to the best of our
ability. There is still a very odd piece of computation in
elf_build_reltab() which I can't really figure out...
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Add something approaching real ELF header files.
Begin merging the common ELF code, beginning with the section name
detection.
Drop automatic generation of .comment section, and in particular the
treatment of .common as a special section (if we decide generating
.comment is still a good idea, we should just do it as a macro.)
Augment the list of known sections, and make it table-driven.
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
