2014-08-22 16:36 GMT+04:00 Martin Liška <mli...@suse.cz>:
> On 08/13/2014 02:25 PM, Ilya Enkovich wrote:
>> Hi,
>>
>> This patch is to fix wrong refactoring for cgraph_node::function_symbol
>> introduced by this patch:
>> https://gcc.gnu.org/ml/gcc-cvs/2014-07/msg00805.html. Here is how function
>> was refactored:
>>
>> -cgraph_function_node (struct cgraph_node *node, enum availability
>> *availability)
>> +cgraph_node *
>> +cgraph_node::function_symbol (enum availability *availability)
>> {
>> + cgraph_node *node = NULL;
>> +
>> do
>> {
>> - node = cgraph_function_or_thunk_node (node, availability);
>> + node = ultimate_alias_target (availability);
>> if (node->thunk.thunk_p)
>> {
>> node = node->callees->callee;
>> if (availability)
>> {
>> enum availability a;
>> - a = cgraph_function_body_availability (node);
>> + a = node->get_availability ();
>> if (a < *availability)
>> *availability = a;
>> }
>> - node = cgraph_function_or_thunk_node (node, availability);
>> + node = node->ultimate_alias_target (availability);
>> }
>> } while (node && node->thunk.thunk_p);
>> return node;
>> }
>>
>> first ultimate_alias_target call always uses 'this' instead of 'node'. This
>> causes infinite loop.
>>
>> Patch was bootstrapped and regtested on linux-x86_64. OK for trunk?
> Hello.
> Thank you for the fix. Unfortunately, there's no test case that would show me
> the problem.
You should have have at least two thunks in a chain of aliases and
thunks to fall into an infinite loop here. I do not know when such
chains exist in regular cases. I hit this bug testing pointer bounds
checker which transforms functions to thunks and therefore get longer
chains of thunks.
Thanks,
Ilya
>
> Martin
>>
>> Thanks,
>> Ilya
>> --
>>
>> 2014-08-13 Ilya Enkovich <ilya.enkov...@intel.com>
>>
>> * cgraph.c (cgraph_node::function_symbol): Fix wrong
>> cgraph_function_node to cgraph_node::function_symbol
>> refactoring.
>>
>> diff --git a/gcc/cgraph.c b/gcc/cgraph.c
>> index 5a0b903..370a96a 100644
>> --- a/gcc/cgraph.c
>> +++ b/gcc/cgraph.c
>> @@ -3000,11 +3000,11 @@ cgraph_node::verify_cgraph_nodes (void)
>> cgraph_node *
>> cgraph_node::function_symbol (enum availability *availability)
>> {
>> - cgraph_node *node = NULL;
>> + cgraph_node *node = this;
>>
>> do
>> {
>> - node = ultimate_alias_target (availability);
>> + node = node->ultimate_alias_target (availability);
>> if (node->thunk.thunk_p)
>> {
>> node = node->callees->callee;
>
