Re: [Crash-utility] fix gdb_get_datatype cannot handle integer type
----- Original Message -----
Dave,
On Wed, Mar 6, 2013 at 10:04 PM, Dave Anderson <anderson(a)redhat.com>
wrote:
>
>
> ----- Original Message -----
>> Hi Dave,
>>
>> Current when pass integer type to gdb_get_datatype in crash, it would return
>> req->typecode=0 and req->length=0.
>>
>> As it only allow TYPE_CODE_ENUM to be passed. here is a patch for fixing it.
>> Do you think it could be merged?
>
> That's the OP_VAR_VALUE section -- what is the command that you're using
that
> ends up passing an integer type to the function? And what problem does it
> cause?
I enhance whatis command in my local code base to show the function's original
variant name.
If not with my change, the original result is:
int schedule_delayed_work_on(int , struct delayed_work * , long unsigned int );
With my change, the result becomes:
int schedule_delayed_work_on(int cpu, struct delayed_work * dwork, long unsigned int
delay);
So it look nicer, right? :)
I guess -- but when I add the patch, it doesn't look any different, so presumably
it only applies w/respect to your enhanced whatis command...
But I meet an issue that whatis is not intent for showing function prototype only, but
for
structure/union/integer type.
So I need to add arg_to_datatype in whatis_variable to tell the passed data's type to
whether
call gdb's function for exacting out the function parameter's name.
Then I face the bug as I reported...
It's not really a bug because that code path was meant for usage by the
enumerator_value() function. So it makes me a bit nervous to modify it
for code that only your enhanced whatis command would ever see.
Would your code work if only the req->typecode and req->length fields where
passed back? (i.e., without tinkering with the req->value and req->tagname
fields in the non-enum case?) Like this:
--- gdb-7.3.1/gdb/symtab.c.orig
+++ gdb-7.3.1/gdb/symtab.c
@@ -5054,8 +5054,9 @@ gdb_get_datatype(struct gnu_request *req
if (gdb_CRASHDEBUG(2))
console("expr->elts[0].opcode: OP_VAR_VALUE\n");
type = expr->elts[2].symbol->type;
+ req->typecode = TYPE_CODE(type);
+ req->length = TYPE_LENGTH(type);
if (TYPE_CODE(type) == TYPE_CODE_ENUM) {
- req->typecode = TYPE_CODE(type);
req->value = SYMBOL_VALUE(expr->elts[2].symbol);
req->tagname = TYPE_TAG_NAME(type);
if (!req->tagname) {
And what exactly do you pass to datatype_info() that would lead to
that code path?
Dave