[review] gdb: fix segfault in overload resolution debug output
Commit Message
Change URL: https://gnutoolchain-gerrit.osci.io/r/c/binutils-gdb/+/734
......................................................................
gdb: fix segfault in overload resolution debug output
A segfault occurs if overload resolution debug mode is turned on via
the 'set debug overload' command. E.g.:
~~~
$ gdb ./a.out
...
(gdb) start
...
(gdb) set debug overload 1
(gdb) print foo(5)
-- Arg is int [8], parm is double [9]
Overloaded function instance (null) # of parms 1
Segmentation fault
$
~~~
The problem is, GDB tries to print the badness vector after it has
been std::move'd. Fix the problem by printing the vector before it is
moved.
gdb/ChangeLog:
2019-11-29 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* valops.c (find_oload_champ): Print part of debug messages
before the badness vector is std::move'd.
Change-Id: Ia623f9637e82ec332bfeac23eb6b0f2ffdcdde27
---
M gdb/valops.c
1 file changed, 25 insertions(+), 23 deletions(-)
Comments
Andrew Burgess has posted comments on this change.
Change URL: https://gnutoolchain-gerrit.osci.io/r/c/binutils-gdb/+/734
......................................................................
Patch Set 1: Code-Review+2
LGTM.
@@ -3023,6 +3023,28 @@
bv = rank_function (parm_types,
args.slice (static_offset));
+ if (overload_debug)
+ {
+ if (methods != NULL)
+ fprintf_filtered (gdb_stderr,
+ "Overloaded method instance %s, # of parms %d\n",
+ methods[ix].physname, (int) parm_types.size ());
+ else if (xmethods != NULL)
+ fprintf_filtered (gdb_stderr,
+ "Xmethod worker, # of parms %d\n",
+ (int) parm_types.size ());
+ else
+ fprintf_filtered (gdb_stderr,
+ "Overloaded function instance "
+ "%s # of parms %d\n",
+ functions[ix]->demangled_name (),
+ (int) parm_types.size ());
+ for (jj = 0; jj < args.size () - static_offset; jj++)
+ fprintf_filtered (gdb_stderr,
+ "...Badness @ %d : %d\n",
+ jj, bv[jj].rank);
+ }
+
if (oload_champ_bv->empty ())
{
*oload_champ_bv = std::move (bv);
@@ -3048,29 +3070,9 @@
break;
}
if (overload_debug)
- {
- if (methods != NULL)
- fprintf_filtered (gdb_stderr,
- "Overloaded method instance %s, # of parms %d\n",
- methods[ix].physname, (int) parm_types.size ());
- else if (xmethods != NULL)
- fprintf_filtered (gdb_stderr,
- "Xmethod worker, # of parms %d\n",
- (int) parm_types.size ());
- else
- fprintf_filtered (gdb_stderr,
- "Overloaded function instance "
- "%s # of parms %d\n",
- functions[ix]->demangled_name (),
- (int) parm_types.size ());
- for (jj = 0; jj < args.size () - static_offset; jj++)
- fprintf_filtered (gdb_stderr,
- "...Badness @ %d : %d\n",
- jj, bv[jj].rank);
- fprintf_filtered (gdb_stderr, "Overload resolution "
- "champion is %d, ambiguous? %d\n",
- oload_champ, oload_ambiguous);
- }
+ fprintf_filtered (gdb_stderr, "Overload resolution "
+ "champion is %d, ambiguous? %d\n",
+ oload_champ, oload_ambiguous);
}
return oload_champ;