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This patch deals with the auto-import feature. There are 2 versions of this feature: the original one, which was piggybacked on the OS loader with an optional help from the runtime (--enable-auto-import --enable-runtime-pseudo-reloc-v1) and is still the one mostly documented in the sources and manual; the enhanced one by Kai Tietz, which is entirely piggybacked on the runtime (--enable-auto-import --enable-runtime-pseudo-reloc-v2) and is the default for Mingw and Cygwin nowadays. The implementation is inefficient because of pe[p]_find_data_imports: for every undefined symbol, the function walks the entire set of relocations for all the input files and does a direct name comparison for each of them. This is easily fixable by using a hash-based map for v1 and a simple hash table for v2. This patch leaves v1 alone and only changes v2. It also factors out pe[p]_find_data_imports into a common function, removes old cruft left and right, and attempts to better separate the implementations of v1 and v2 in the code. ld/ * emultempl/pe.em (U_SIZE): Delete. (pe_data_import_dll): Likewise. (make_import_fixup): Return void, take 4th parameter and pass it down in call to pe_create_import_fixup. (pe_find_data_imports): Move to... (gld_${EMULATION_NAME}_after_open): Run the stdcall fixup pass after the auto-import pass and add a guard before running the latter. * emultempl/pep.em (U_SIZE): Delete. (pep_data_import_dll): Likewise. (make_import_fixup): Return void, take 4th parameter and pass it down in call to pe_create_import_fixup. (pep_find_data_imports): Move to... (gld_${EMULATION_NAME}_after_open): Run the stdcall fixup pass after the auto-import pass and add a guard before running the latter. * pe-dll.c (runtime_pseudp_reloc_v2_init): Change type to bfd_boolean. (pe_walk_relocs_of_symbol): Rename into... (pe_walk_relocs): ...this. Add 2 more parameters,4th parameter to the callback prototype and pass 4th parameter in calls to the callback. If the import hash table is present, invoke the callback on the reloc if the symbol name is in the table. (pe_find_data_imports): ...here. Take 2 parameters. Build an import hash table for the pseudo-relocation support version 2. When it is built, walk the relocations only once at the end; when it is not, do not build a fixup when the symbol isn't part of an import table. Issue the associated warning only after a first fixup is built. (tmp_seq2): Delete. (make_singleton_name_imp): Likewise. (make_import_fixup_mark): Return const char * and a stable string. (make_import_fixup_entry): Do not deal with the pseudo-relocation support version 2. (make_runtime_pseudo_reloc): Factor out code and fix formatting. (pe_create_import_fixup): Add 5th parameter. Clearly separate the pseudo-relocation support version 2 from the rest. Fix formatting. * pe-dll.h (pe_walk_relocs_of_symbol): Delete. (pe_find_data_imports): Declare. (pe_create_import_fixup): Add 5th parameter. * pep-dll.c (pe_data_import_dll): Delete. (pe_find_data_imports): Define. (pe_walk_relocs_of_symbol): Delete. * pep-dll.h (pep_walk_relocs_of_symbol): Delete. (pep_find_data_imports): Declare. (pep_create_import_fixup): Add 5th parameter. * ld.texinfo (--enable-auto-import): Adjust to new implementation. |
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.. | ||
emulparams | ||
emultempl | ||
po | ||
scripttempl | ||
testsuite | ||
.gitignore | ||
aclocal.m4 | ||
ChangeLog | ||
ChangeLog-0001 | ||
ChangeLog-0203 | ||
ChangeLog-2004 | ||
ChangeLog-2005 | ||
ChangeLog-2006 | ||
ChangeLog-2007 | ||
ChangeLog-2008 | ||
ChangeLog-2009 | ||
ChangeLog-2010 | ||
ChangeLog-2011 | ||
ChangeLog-2012 | ||
ChangeLog-2013 | ||
ChangeLog-2014 | ||
ChangeLog-2015 | ||
ChangeLog-2016 | ||
ChangeLog-2017 | ||
ChangeLog-9197 | ||
ChangeLog-9899 | ||
config.in | ||
configure | ||
configure.ac | ||
configure.host | ||
configure.tgt | ||
deffile.h | ||
deffilep.y | ||
dep-in.sed | ||
elf-hints-local.h | ||
fdl.texi | ||
gen-doc.texi | ||
genscrba.sh | ||
genscripts.sh | ||
h8-doc.texi | ||
ld.h | ||
ld.texinfo | ||
ldbuildid.c | ||
ldbuildid.h | ||
ldcref.c | ||
ldctor.c | ||
ldctor.h | ||
ldemul.c | ||
ldemul.h | ||
ldexp.c | ||
ldexp.h | ||
ldfile.c | ||
ldfile.h | ||
ldgram.y | ||
ldint.texinfo | ||
ldlang.c | ||
ldlang.h | ||
ldlex-wrapper.c | ||
ldlex.h | ||
ldlex.l | ||
ldmain.c | ||
ldmain.h | ||
ldmisc.c | ||
ldmisc.h | ||
ldver.c | ||
ldver.h | ||
ldwrite.c | ||
ldwrite.h | ||
lexsup.c | ||
MAINTAINERS | ||
Makefile.am | ||
Makefile.in | ||
mri.c | ||
mri.h | ||
NEWS | ||
pe-dll.c | ||
pe-dll.h | ||
pep-dll.c | ||
pep-dll.h | ||
plugin.c | ||
plugin.h | ||
README | ||
stamp-h.in | ||
sysdep.h | ||
testplug2.c | ||
testplug3.c | ||
testplug4.c | ||
testplug.c | ||
TODO |
README for LD
This is the GNU linker. It is distributed with other "binary
utilities" which should be in ../binutils. See ../binutils/README for
more general notes, including where to send bug reports.
There are many features of the linker:
* The linker uses a Binary File Descriptor library (../bfd)
that it uses to read and write object files. This helps
insulate the linker itself from the format of object files.
* The linker supports a number of different object file
formats. It can even handle multiple formats at once:
Read two input formats and write a third.
* The linker can be configured for cross-linking.
* The linker supports a control language.
* There is a user manual (ld.texinfo), as well as the
beginnings of an internals manual (ldint.texinfo).
Installation
============
See ../binutils/README.
If you want to make a cross-linker, you may want to specify
a different search path of -lfoo libraries than the default.
You can do this by setting the LIB_PATH variable in ./Makefile
or using the --with-lib-path configure switch.
To build just the linker, make the target all-ld from the top level
directory (one directory above this one).
Porting to a new target
=======================
See the ldint.texinfo manual.
Reporting bugs etc
===========================
See ../binutils/README.
Known problems
==============
The Solaris linker normally exports all dynamic symbols from an
executable. The GNU linker does not do this by default. This is
because the GNU linker tries to present the same interface for all
similar targets (in this case, all native ELF targets). This does not
matter for normal programs, but it can make a difference for programs
which try to dlopen an executable, such as PERL or Tcl. You can make
the GNU linker export all dynamic symbols with the -E or
--export-dynamic command line option.
HP/UX 9.01 has a shell bug that causes the linker scripts to be
generated incorrectly. The symptom of this appears to be "fatal error
- scanner input buffer overflow" error messages. There are various
workarounds to this:
* Build and install bash, and build with "make SHELL=bash".
* Update to a version of HP/UX with a working shell (e.g., 9.05).
* Replace "(. ${srcdir}/scripttempl/${SCRIPT_NAME}.sc)" in
genscripts.sh with "sh ${srcdir}..." (no parens) and make sure the
emulparams script used exports any shell variables it sets.
Copyright (C) 2012-2018 Free Software Foundation, Inc.
Copying and distribution of this file, with or without modification,
are permitted in any medium without royalty provided the copyright
notice and this notice are preserved.