On 09/07/18 08:51, Bernd Edlinger wrote:
> On 09/07/18 00:26, Jeff Law wrote:
>> On 09/06/2018 04:16 PM, Jeff Law wrote:
>>> On 09/06/2018 04:01 PM, Jeff Law wrote:
>>>> On 09/06/2018 11:12 AM, Bernd Edlinger wrote:
>>>>
>>>>>>
>>>>>
>>>>> Ah, thanks a lot.
>>>>>
>>>>> Okay, this is the status of the STRING-CST semantic-v2 patches:
>>>>>
>>>>> [PATCH] Check the STRING_CSTs in varasm.c
>>>>> https://gcc.gnu.org/ml/gcc-patches/2018-08/msg01569.html
>>>>> => Unfortunately I forgot to change the Title to [PATCHv2] or so.
>>>>> Should I send a ping for this one?
>>>>>
>>>>> [PATCHv2] Handle overlength strings in the C FE
>>>>> https://gcc.gnu.org/ml/gcc-patches/2018-08/msg01566.html
>>>>> => Should I send a ping for this one?
>>>> No need to ping. I've got it here. What's odd is that it's regressing
>>>> 87053 .
>>> Which is probably a sign that we've got an incorrect test for NUL
>>> termination somewhere.
>
> It may be a sign that we should first fix the low level functions
> before the high level stuff.
>
>> I think I've found the issue. I've got more testing to do, but looks
>> like a thinko on my part.
>>
>
> Ah, I forgot, the regression on pr87053 and fortran.dg/pr45636.f90
> is fixed by this patch:
>
> [PATCH] Adjust c_getstr/c_strlen to new STRING_CST semantic
> https://gcc.gnu.org/ml/gcc-patches/2018-08/msg02013.html
>
> This is a new regression since the patch was initially posted.
>
Well, actually both patches seem to have a circular dependency.
If you want we can break this dependency by adding this to the c_getstr patch:
--- gcc/fold-const.c 2018-09-07 14:22:50.047964775 +0200
+++ gcc/fold-const.c 2018-09-07 15:06:46.656989904 +0200
@@ -14611,6 +14611,10 @@ c_getstr (tree src, unsigned HOST_WIDE_I
unsigned HOST_WIDE_INT string_length = TREE_STRING_LENGTH (src);
unsigned HOST_WIDE_INT string_size = tree_to_uhwi (mem_size);
+ /* Ideally this would turn into a gcc_checking_assert over time. */
+ if (string_length > string_size)
+ return NULL;
+
const char *string = TREE_STRING_POINTER (src);
if (string_length == 0
This should allow it to work with current semantics as well.
Bernd.
