Binutils with MCST patches
79188d8d27
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. |
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bfd | ||
binutils | ||
config | ||
cpu | ||
elfcpp | ||
etc | ||
gas | ||
gdb | ||
gold | ||
gprof | ||
include | ||
intl | ||
ld | ||
libdecnumber | ||
libiberty | ||
opcodes | ||
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.