2b5b9d09ed
Our testsuite noticed a crash when trying to call a function which
requires GDB to allocate memory in the inferior. Typically, this
happens when one of the parameters is a string. For instance, our
testcase tries:
(gdb) call debug.trace (me, "You")
[1] 32737 segmentation fault /path/to/gdb
What happens is that GDB sees the string, and thus tries to allocate
memory for it in the inferior:
> /* Allocate NBYTES of space in the inferior using the inferior's
> malloc and return a value that is a pointer to the allocated
> space. */
>
> struct value *
> value_allocate_space_in_inferior (int len)
> {
> struct objfile *objf;
> struct value *val = find_function_in_inferior ("malloc", &objf);
And find_function_in_inferior first searches the symtab in case
we have debug info. But, in our case (bareboard powerpc), we don't,
so it gets "malloc"'s address from the minimal symbols, and builds
a value whose type is a TYPE_CODE_PTR, not a TYPE_CODE_FUNC.
As a result, when we later try to make the call to malloc, we end up
inside the powerpc tdep code that has:
> do_ppc_sysv_return_value (struct gdbarch *gdbarch, struct type *func_type,
[...]
> if (func_type
> && TYPE_CALLING_CONVENTION (func_type) == DW_CC_GDB_IBM_OpenCL)
The problem is that func_type is not a TYPE_CODE_FUNC, and thus
the type-specific kind is not TYPE_SPECIFIC_FUNC, and so we do
TYPE_CALLING_CONVENTION is an invalid access.
Interestingly, the other call to TYPE_CALLING_CONVENTION is correctly
preceded by a check of the type's TYPE_CODE (making sure that it is
TYPE_CODE_FUNC).
gdb/ChangeLog:
* ppc-sysv-tdep.c (do_ppc_sysv_return_value): Do not check
FUNC_TYPE's calling convention if FUNC_TYPE is not a function.
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.