ef9d256562
2021-05-31 Nelson Chu <nelson.chu@sifive.com>
Lifang Xia <lifang_xia@c-sky.com>
The data segment phase exp_seg_relro_adjust means we are still adjusting the
relro segments, so we will get the symbol values which havn't consider the
relro. It is dangerous and we shouldn't do the relaxations at this stage.
Otherwise, we may get the truncated fails when the relax range crossing the
data segment.
One of the solution is that, we use a pointer to monitor the data segment
phase while relaxing, to know whether the relro has been handled or not.
Once we check the phase is exp_seg_relro_adjust, we should skip this round
of relaxations, since the incorrect symbol values will affect the correctness
of relaxations. I think we probably need to record more information about
data segment or alignments in the future, to make sure it is safe to doing
relaxations.
For the two new testcases, relro-relax-lui and relro-relax-pcrel, we get
the following truncated errors when using toolchains, which enable relro:
(.text+0x0): relocation truncated to fit: R_RISCV_GPREL_I against symbol `SymbolRodata' defined in .rodata section in test1.o
After applying this patch, the truncated errors should be resolved.
However, only linux toolchains support -z relro, so we only test these
two testcases when supporting shared library.
bfd/
PR 27566
* elfnn-riscv.c (struct riscv_elf_link_hash_table): New integer pointer
to monitor the data segment phase.
(bfd_elfNN_riscv_set_data_segment_info): New function called by
after_allocation, to set the data_segment_phase from expld.dataseg.
(_bfd_riscv_relax_section): Don't relax when data_segment_phase is
exp_seg_relro_adjust (0x4).
* elfxx-riscv.h (bfd_elf32_riscv_set_data_segment_info): New extern.
(bfd_elf64_riscv_set_data_segment_info): Likewise.
ld/
PR 27566
* emultempl/riscvelf.em (after_allocation): Call
riscv_set_data_segment_info to set data segment phase before relaxing.
* testsuite/ld-riscv-elf/ld-riscv-elf.exp: Updated.
* testsuite/ld-riscv-elf/relro-relax-lui.d: New testcase.
* testsuite/ld-riscv-elf/relro-relax-lui.s: Likewise.
* testsuite/ld-riscv-elf/relro-relax-pcrel.d: Likewise.
* testsuite/ld-riscv-elf/relro-relax-pcrel.s: Likewise.
README for GNU development tools This directory contains various GNU compilers, assemblers, linkers, debuggers, etc., plus their support routines, definitions, and documentation. If you are receiving this as part of a GDB release, see the file gdb/README. If with a binutils release, see binutils/README; if with a libg++ release, see libg++/README, etc. That'll give you info about this package -- supported targets, how to use it, how to report bugs, etc. It is now possible to automatically configure and build a variety of tools with one command. To build all of the tools contained herein, run the ``configure'' script here, e.g.: ./configure make To install them (by default in /usr/local/bin, /usr/local/lib, etc), then do: make install (If the configure script can't determine your type of computer, give it the name as an argument, for instance ``./configure sun4''. You can use the script ``config.sub'' to test whether a name is recognized; if it is, config.sub translates it to a triplet specifying CPU, vendor, and OS.) If you have more than one compiler on your system, it is often best to explicitly set CC in the environment before running configure, and to also set CC when running make. For example (assuming sh/bash/ksh): CC=gcc ./configure make A similar example using csh: setenv CC gcc ./configure make Much of the code and documentation enclosed is copyright by the Free Software Foundation, Inc. See the file COPYING or COPYING.LIB in the various directories, for a description of the GNU General Public License terms under which you can copy the files. REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info on where and how to report problems.