Binutils with MCST patches
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Joel Brobecker cc0e770c0d memory error printing component of record from convenience variable
Consider the following situation Ada code:

   type Kind_T is (One, Two, Three);
   type Time_Set_T is array (Kind_T) of Integer;

   type T  is record
      Started    : Time_Set_T;
   end record;

   Null_T : constant T := (Started => (others => 0));

   My_Item : Pck.T := Pck.Null_T;

Trying to print the value of My_Item.Started is no problem:

    (gdb) p item.started
    $1 = (0, 0, 0)

However, if you save My_Item into a convenience variable first,
and then try to print a component of that record, you get
an unexpected memory error, instead of getting the same result.
For instance:

    (gdb) set variable $item := item
    (gdb) p $item.started
    Cannot access memory at address 0x0

The issue occurs when, after we extracted the component from
the convenience variable, we next try to "fix" it (which is
ada-lang speak for resolving the type into a static type).
This is done in ada_to_fixed_value, which delegates to
ada_to_fixed_value_create via:

    val = ada_to_fixed_value_create (value_type (val),
                                     value_address (val), val);

And looking at ada_to_fixed_value_create, we see that:

  struct type *type = ada_to_fixed_type (type0, 0, address, NULL, 1);

  if (type == type0 && val0 != NULL)
    return val0;
  else
    return value_from_contents_and_address (type, 0, address);

The part that interests us, in this case, is the "else" branch,
where we obviously make the implicit assumption that our object
has an address, which is not true, in this case, because we are
actually dealing with a convenience variable.

This patch plugs that hole by adding special handing for situations
where val does not live in memory. In that case, we just create
a not_lval value using val's contents.

gdb/ChangeLog:

        * ada-lang.c (ada_to_fixed_value_create): Add handling of
        the case where VALUE_LVAL (val0) is not lval_memory.

gdb/testsuite/ChangeLog:

        * gdb.ada/convvar_comp: New testcase.

Tested on x86_64-linux.
2018-01-05 02:41:28 -05:00
bfd Automatic date update in version.in 2018-01-05 00:00:35 +00:00
binutils Fix compile time warning introduced by previous delta. 2018-01-03 17:32:59 +00:00
config
cpu
elfcpp Update year range in copyright notice of binutils files 2018-01-03 17:49:56 +10:30
etc Update year range in copyright notice of binutils files 2018-01-03 17:49:56 +10:30
gas RISC-V: Add 2 missing privileged registers. 2018-01-04 14:17:53 -08:00
gdb memory error printing component of record from convenience variable 2018-01-05 02:41:28 -05:00
gold Update year range in copyright notice of binutils files 2018-01-03 17:49:56 +10:30
gprof Update year range in copyright notice of binutils files 2018-01-03 17:49:56 +10:30
include RISC-V: Add 2 missing privileged registers. 2018-01-04 14:17:53 -08:00
intl Require ngettext in test of system gettext implementation 2017-11-07 15:56:44 +10:30
ld Update year range in copyright notice of binutils files 2018-01-03 17:49:56 +10:30
libdecnumber
libiberty Sync libiberty/ & include/ with GCC 2017-09-15 17:40:33 +01:00
opcodes Update year range in copyright notice of binutils files 2018-01-03 17:49:56 +10:30
readline
sim Fix compile time warning (in the ARM simulator) about a print statement with insufficient arguments. 2018-01-02 17:15:16 +00:00
texinfo
zlib
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.gitignore
ChangeLog Update the address of the FSF in the copyright notice of files which were using the old address. 2017-12-14 12:48:55 +00:00
compile
config-ml.in
config.guess
config.rpath
config.sub
configure Add gdb for or1k build 2017-12-12 23:39:28 +09:00
configure.ac Add gdb for or1k build 2017-12-12 23:39:28 +09:00
COPYING
COPYING3
COPYING3.LIB
COPYING.LIB
COPYING.LIBGLOSS Update the address of the FSF in the copyright notice of files which were using the old address. 2017-12-14 12:48:55 +00:00
COPYING.NEWLIB
depcomp
djunpack.bat
install-sh
libtool.m4
lt~obsolete.m4
ltgcc.m4
ltmain.sh
ltoptions.m4
ltsugar.m4
ltversion.m4
MAINTAINERS
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src-release.sh Add -l option to src-release script. 2017-09-15 16:18:20 +01:00
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		   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.