Binutils with MCST patches
Go to file
Pedro Alves 79188d8d27 Fix resolving GNU ifunc bp locations when inferior runs resolver
I noticed that if you set a breakpoint on an ifunc before the ifunc is
resolved, and then let the program call the ifunc, thus resolving it,
GDB end up with a location for that original breakpoint that is
pointing to the ifunc target, but it is left pointing to the first
address of the function, instead of after its prologue.  After
prologue is what you get if you create a new breakpoint at that point.

1) With no debug info for the target function:

  1.a) Set before resolving, and then program continued passed resolving:

    Num     Type           Disp Enb Address            What
    1       breakpoint     keep y   0x0000000000400753 <final>

  1.b) Breakpoint set after inferior resolved ifunc:

    Num     Type           Disp Enb Address            What
    2       breakpoint     keep y   0x0000000000400757 <final+4>


2) With debug info for the target function:

   1.a) Set before resolving, and then program continued passed resolving:

     Num     Type           Disp Enb Address            What
     1       breakpoint     keep y   0x0000000000400753 in final at gdb/testsuite/gdb.base/gnu-ifunc-final.c:20

   1.b) Breakpoint set after inferior resolved ifunc:

     Num     Type           Disp Enb Address            What
     2       breakpoint     keep y   0x000000000040075a in final at gdb/testsuite/gdb.base/gnu-ifunc-final.c:21

The problem is that elf_gnu_ifunc_resolver_return_stop (called by the
internal breakpoint that traps the resolver returning) does not agree
with linespec.c:minsym_found.  It does not skip to the function's
start line (i.e., past the prologue).  We can now use the
find_function_start_sal overload added by the previous commmit to fix
this.

New tests included, which fail before the patch, and pass afterwards.

gdb/ChangeLog:
2018-04-26  Pedro Alves  <palves@redhat.com>

	* elfread.c (elf_gnu_ifunc_resolver_return_stop): Use
	find_function_start_sal instead of find_pc_line.

gdb/testsuite/ChangeLog:
2018-04-26  Pedro Alves  <palves@redhat.com>

	* gdb.base/gnu-ifunc.exp (set-break): Test that GDB resolves
	ifunc breakpoint locations correctly of ifunc breakpoints set
	while the program resolves the ifunc.
2018-04-26 13:12:09 +01:00
bfd PPC64: always make synthetic .text symbols for GNU ifunc symbols 2018-04-26 13:09:40 +01:00
binutils [ARM] FDPIC: Update testsuite so that many tests pass with arm*-uclinuxfdpiceabi. 2018-04-25 21:13:14 +00:00
config config: Sync with GCC 2018-04-05 15:22:13 -07:00
cpu opcodes error messages 2018-03-03 11:34:26 +10:30
elfcpp PowerPC inline PLT call support 2018-04-09 17:25:20 +09:30
etc
gas x86: fold various non-memory operand AVX512VL templates 2018-04-26 08:55:02 +02:00
gdb Fix resolving GNU ifunc bp locations when inferior runs resolver 2018-04-26 13:12:09 +01:00
gold Fix bug with relocation addends and merge sections with --icf. 2018-04-24 22:13:56 -07:00
gprof Updated Spanish translation for gprof directory 2018-04-18 12:02:17 +01:00
include [ARM] Add TLS relocations for FDPIC. 2018-04-25 20:57:02 +00:00
intl
ld [ARM] FDPIC: Update testsuite so that many tests pass with arm*-uclinuxfdpiceabi. 2018-04-25 21:13:14 +00:00
libdecnumber
libiberty Resync libiberty sources with master version in GCC repository. 2018-04-17 13:53:38 +01:00
opcodes x86: fold various non-memory operand AVX512VL templates 2018-04-26 08:55:02 +02:00
readline
sim
texinfo
zlib
.cvsignore
.gitattributes
.gitignore
ChangeLog
compile
config-ml.in
config.guess
config.rpath
config.sub
configure
configure.ac
COPYING
COPYING3
COPYING3.LIB
COPYING.LIB
COPYING.LIBGLOSS
COPYING.NEWLIB
depcomp
djunpack.bat
install-sh
libtool.m4
lt~obsolete.m4
ltgcc.m4
ltmain.sh
ltoptions.m4
ltsugar.m4
ltversion.m4
MAINTAINERS
Makefile.def
Makefile.in
Makefile.tpl
makefile.vms
missing
mkdep
mkinstalldirs
move-if-change
README
README-maintainer-mode
setup.com
src-release.sh
symlink-tree
ylwrap

		   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.