mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-12 09:58:36 +00:00
517d9fc653
__start_SECNAME and __stop_SECNAME symbols are automatically generated by ld for orphan sections, i.e. those not explicitely referenced by a linker script. The symbols are supposed to be placed correspondingly at the start and the end of the section in output file. In some cases __start_SECNAME may be placed at the address after the end of the previous section (if any) and before the start the section. This happens when following conditions are met: 1. the orphan section is found in more than one input file 2. the orphan section has different alignment requirements across input files 3. the first instance of the section encountered doesn't have the greatest alignment requirement In these conditions resulting output section will be placed at address after the end of the previous section aligned to the greatest alignment requirement in the inputs, but __start_SECNAME will be placed at address after the end of the previous section aligned to the alignment requirement of the first input in which the section is encountered. See commit message of r196118 for a concrete example of problems caused by this bug. The fix is to place __start_SECNAME inside the section and use ABSOLUTE directive, rather than placing __start_SECNAME outside the section and trying to guess address alignment. This fix is in line with upstream binutils change/fix made between versions 2.19 and 2.20 in revision of 1.307 ldlang.c. MFC after: 3 weeks |
||
|---|---|---|
| .. | ||
| emulparams | ||
| emultempl | ||
| po | ||
| scripttempl | ||
| acinclude.m4 | ||
| aclocal.m4 | ||
| ChangeLog | ||
| ChangeLog-0001 | ||
| ChangeLog-0203 | ||
| ChangeLog-9197 | ||
| ChangeLog-9899 | ||
| config.in | ||
| configure | ||
| configure.host | ||
| configure.in | ||
| configure.tgt | ||
| deffile.h | ||
| deffilep.y | ||
| dep-in.sed | ||
| fdl.texi | ||
| gen-doc.texi | ||
| genscripts.sh | ||
| h8-doc.texi | ||
| ld.1 | ||
| ld.h | ||
| ld.texinfo | ||
| 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.h | ||
| ldlex.l | ||
| ldmain.c | ||
| ldmain.h | ||
| ldmisc.c | ||
| ldmisc.h | ||
| ldver.c | ||
| ldver.h | ||
| ldver.texi | ||
| ldwrite.c | ||
| ldwrite.h | ||
| lexsup.c | ||
| MAINTAINERS | ||
| Makefile.am | ||
| Makefile.in | ||
| mri.c | ||
| mri.h | ||
| NEWS | ||
| pe-dll.c | ||
| pe-dll.h | ||
| README | ||
| stamp-h.in | ||
| sysdep.h | ||
| 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.