Build failure with probe patch
Commit Message
On Thu, 2015-02-19 at 18:37 +0100, Jose E. Marchesi wrote:
> I see, void is not allowed to alias a char... we are doomed! :D
>
> Oh well, I guess we will have to use an union to avoid any possible
> strict-aliasing warning... Can we assume C99 in GDB?
Even with this issue fixed I ran into one other compiler problem. I get
this error from GCC 4.1.2:
cc1: warnings being treated as errors
/scratch/sellcey/gdb-bug/src/gdb/gdb/dtrace-probe.c: In function 'dtrace_get_probes':
/scratch/sellcey/gdb-bug/src/gdb/gdb/dtrace-probe.c:64: warning: 'arg.expr' is used uninitialized in this function
To fix this problem I changed dtrace_process_dof_probe to have
'arg.expr = NULL' in the loop that stores argument descriptions. Here
is a complete patch that compiled for me using the old GCC.
Steve Ellcey
sellcey@imgtec.com
Comments
To fix this problem I changed dtrace_process_dof_probe to have
'arg.expr = NULL' in the loop that stores argument descriptions. Here
is a complete patch that compiled for me using the old GCC.
Ah! But the warning seems all misplaced, isnt it? Weird... :D
diff --git a/gdb/dtrace-probe.c b/gdb/dtrace-probe.c
index a6544ba..fd6ae6e 100644
--- a/gdb/dtrace-probe.c
+++ b/gdb/dtrace-probe.c
@@ -415,6 +415,7 @@ dtrace_process_dof_probe (struct objfile *objfile,
struct dtrace_probe_arg arg;
struct expression *expr;
+ arg.expr = NULL;
I would add a comment explaining why that sentence is necessary, as it
is not obvious at all to the casual reader.
arg.type_str = xstrdup (p);
/* Use strtab_size as a sentinel. */
@@ -617,17 +618,17 @@ dtrace_get_probes (VEC (probe_p) **probesp, struct objfile *objfile)
{
if (elf_section_data (sect)->this_hdr.sh_type == SHT_SUNW_dof)
{
- struct dtrace_dof_hdr *dof;
+ bfd_byte *dof;
/* Read the contents of the DOF section and then process it to
extract the information of any probe defined into it. */
- if (!bfd_malloc_and_get_section (abfd, sect, (bfd_byte **) &dof))
+ if (!bfd_malloc_and_get_section (abfd, sect, &dof))
complaint (&symfile_complaints,
_("could not obtain the contents of"
"section '%s' in objfile `%s'."),
sect->name, abfd->filename);
- dtrace_process_dof (sect, objfile, probesp, dof);
+ dtrace_process_dof (sect, objfile, probesp, (struct dtrace_dof_hdr *) dof);
xfree (dof);
}
}
This looks good to me.
Hi Steve,
Thanks for the patch. And thanks Jose and Pedro taking care of this.
On Thursday, February 19 2015, Jose E. Marchesi wrote:
> To fix this problem I changed dtrace_process_dof_probe to have
> 'arg.expr = NULL' in the loop that stores argument descriptions. Here
> is a complete patch that compiled for me using the old GCC.
>
> Ah! But the warning seems all misplaced, isnt it? Weird... :D
Totally :-).
> diff --git a/gdb/dtrace-probe.c b/gdb/dtrace-probe.c
> index a6544ba..fd6ae6e 100644
> --- a/gdb/dtrace-probe.c
> +++ b/gdb/dtrace-probe.c
> @@ -415,6 +415,7 @@ dtrace_process_dof_probe (struct objfile *objfile,
> struct dtrace_probe_arg arg;
> struct expression *expr;
>
> + arg.expr = NULL;
>
> I would add a comment explaining why that sentence is necessary, as it
> is not obvious at all to the casual reader.
Agreed.
> arg.type_str = xstrdup (p);
>
> /* Use strtab_size as a sentinel. */
> @@ -617,17 +618,17 @@ dtrace_get_probes (VEC (probe_p) **probesp, struct objfile *objfile)
> {
> if (elf_section_data (sect)->this_hdr.sh_type == SHT_SUNW_dof)
> {
> - struct dtrace_dof_hdr *dof;
> + bfd_byte *dof;
>
> /* Read the contents of the DOF section and then process it to
> extract the information of any probe defined into it. */
> - if (!bfd_malloc_and_get_section (abfd, sect, (bfd_byte **) &dof))
> + if (!bfd_malloc_and_get_section (abfd, sect, &dof))
> complaint (&symfile_complaints,
> _("could not obtain the contents of"
> "section '%s' in objfile `%s'."),
> sect->name, abfd->filename);
>
> - dtrace_process_dof (sect, objfile, probesp, dof);
> + dtrace_process_dof (sect, objfile, probesp, (struct dtrace_dof_hdr *) dof);
> xfree (dof);
> }
> }
>
> This looks good to me.
This is OK with a ChangeLog entry, and after you address Jose's request.
@@ -415,6 +415,7 @@ dtrace_process_dof_probe (struct objfile *objfile,
struct dtrace_probe_arg arg;
struct expression *expr;
+ arg.expr = NULL;
arg.type_str = xstrdup (p);
/* Use strtab_size as a sentinel. */
@@ -617,17 +618,17 @@ dtrace_get_probes (VEC (probe_p) **probesp, struct objfile *objfile)
{
if (elf_section_data (sect)->this_hdr.sh_type == SHT_SUNW_dof)
{
- struct dtrace_dof_hdr *dof;
+ bfd_byte *dof;
/* Read the contents of the DOF section and then process it to
extract the information of any probe defined into it. */
- if (!bfd_malloc_and_get_section (abfd, sect, (bfd_byte **) &dof))
+ if (!bfd_malloc_and_get_section (abfd, sect, &dof))
complaint (&symfile_complaints,
_("could not obtain the contents of"
"section '%s' in objfile `%s'."),
sect->name, abfd->filename);
- dtrace_process_dof (sect, objfile, probesp, dof);
+ dtrace_process_dof (sect, objfile, probesp, (struct dtrace_dof_hdr *) dof);
xfree (dof);
}
}