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Symbols defined in PIE should be bound locally, the same as -shared -Bsymbolic. Port x86 commit4e0c91e454("Bind defined symbol locally in PIE") change of relocate_section as well as linker tests to s390. Similar as done for other architectures with the following commits: - AArch64:ac33b731d2("[AArch64] Bind defined symbol locally in PIE") - ARM:1dcb9720d6("[ARM] Bind defined symbol locally in PIE") - RISC-V:39c7793ba8("RISC-V: Bind defined symbol locally in PIE") - x86:4e0c91e454("Bind defined symbol locally in PIE") With this change symbols defined in an executable (i.e. PDE or PIE) are bound locally, as they cannot be interposed. In the same way as symbols defined in a shared library linked with -Bsymbolic are bound locally. This also ensures that all defined symbols are bound locally in static PIE. Do not port the x86 change of check_relocs (now scan_relocs). None of the linker tests where the change in condition triggers (e.g. bootstrap, cdtest) produce different readelf -Wa output. The change appears to affect accounting of space required for dynamic relocations. Instead of accounting them in check_relocs and later filtering them away in allocate_dynrelocs, they would not get accounted in the first place: The change in the expression would only have an effect if the following conditions are all met in addition to PIE: ALLOC, PC-relative relocation, global symbol, not defined weak, and defined regular. In this specific case the accounting of the PC relative relocation in h->dyn_relocs would be skipped for PIE. But allocate_dynrelocs later eliminates any PC-relative dynamic relocations if PIC (= PIE or shared library) and SYMBOL_CALLS_LOCAL. bfd/ PR ld/33141 * elf64-s390.c (elf_s390_relocate_section): Bind defined symbol locally in PIE. ld/testsuite/ PR ld/33141 * ld-s390/s390.exp: Add pr33141 tests. * ld-s390/pr33141.rd: New file. * ld-s390/pr33141a.s: Likewise. * ld-s390/pr33141b.s: Likewise. Signed-off-by: Jens Remus <jremus@linux.ibm.com>
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.texi), as well as the
beginnings of an internals manual (ldint.texi).
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.texi 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) 2012-2025 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.