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When evaluating and expression containing UNOP_IND in mode EVAL_AVOID_SIDE_EFFECTS, GDB currently (mostly) returns the result of a call to value_zero meaning we get back an object with the correct type, but its contents are all zero. If the target type contains fields with dynamic type then in order to resolve these dynamic fields GDB will need to read the value of the field from within the parent object. In this case the field value will be zero as a result of the call to value_zero mentioned above. The idea behind EVAL_AVOID_SIDE_EFFECTS is to avoid the chance that doing something like `ptype` will modify state within the target, for example consider: ptype i++. However, there is already precedence within GDB that sometimes, in order to get accurate type results, we can't avoid reading from the target, even when EVAL_AVOID_SIDE_EFFECTS is in effect. For example I would point to eval.c:evaluate_var_value, the handling of OP_REGISTER, the handling of value_x_unop in many places. I believe the Ada expression evaluator also ignore EVAL_AVOID_SIDE_EFFECTS in some cases. I am therefor proposing that, in the case where a pointer points at a dynamic type, we allow UNOP_IND to perform the actual indirection. This allows accurate types to be displayed in more cases. gdb/ChangeLog: * eval.c (evaluate_subexp_standard): Call value_ind for points to dynamic types in UNOP_IND. gdb/testsuite/ChangeLog: * gdb.fortran/pointer-to-pointer.exp: Additional tests.
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.