Re: [Crash-utility] fix gdb_get_datatype cannot handle integer type

Dave, On Thu, Mar 7, 2013 at 12:56 AM, Dave Anderson <anderson(a)redhat.com&gt; wrote: > > > ----- Original Message ----- >> Dave, >> >> On Wed, Mar 6, 2013 at 10:04 PM, Dave Anderson >> <anderson(a)redhat.com&gt; >> 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) { > This seems also works for me.