alignof(int[]) (was Re: [C++ Patch] PR 51316)
On 12/28/2011 07:07 PM, Paolo Carlini wrote: I think the resolution of core/930 and C++11 itself are pretty clear: alignof of an array of unknown bound is fine, provided the element type is complete of course. I think it makes sense for this change to apply to C as well, on the same principle that an array of unknown bound does have known alignment. C maintainers? Jason
Re: alignof(int[]) (was Re: [C++ Patch] PR 51316)
Hi, On 12/30/2011 06:27 PM, Jason Merrill wrote: On 12/28/2011 07:07 PM, Paolo Carlini wrote: I think the resolution of core/930 and C++11 itself are pretty clear: alignof of an array of unknown bound is fine, provided the element type is complete of course. I think it makes sense for this change to apply to C as well, on the same principle that an array of unknown bound does have known alignment. C maintainers? FWIW, I also think it would make sense but - I'm not sure whether you went through the audit trail - Joseph maintained in Comment #3 that C1X is pretty clear about a required diagnostics. Paolo.
Re: alignof(int[]) (was Re: [C++ Patch] PR 51316)
On Fri, 30 Dec 2011, Jason Merrill wrote: On 12/28/2011 07:07 PM, Paolo Carlini wrote: I think the resolution of core/930 and C++11 itself are pretty clear: alignof of an array of unknown bound is fine, provided the element type is complete of course. I think it makes sense for this change to apply to C as well, on the same principle that an array of unknown bound does have known alignment. C maintainers? In the absence of a resolution of a DR against C11 that allows alignof in this case, I think we should continue to disallow it for C. -- Joseph S. Myers jos...@codesourcery.com
Re: alignof(int[]) (was Re: [C++ Patch] PR 51316)
On 12/30/2011 12:38 PM, Joseph S. Myers wrote: In the absence of a resolution of a DR against C11 that allows alignof in this case, I think we should continue to disallow it for C. Ah, I didn't realize that C11 had alignof as well. OK, then. Jason
[C++ Patch] PR 51316
Hi,
I think the resolution of core/930 and C++11 itself are pretty clear:
alignof of an array of unknown bound is fine, provided the element type
is complete of course.
Tested x86_64-linux.
Thanks,
Paolo.
//
/c-family
2011-12-29 Paolo Carlini paolo.carl...@oracle.com
PR c++/51316
* c-common.c (c_sizeof_or_alignof_type): In C++ allow for alignof
of array types with an unknown bound.
/testsuite
2011-12-29 Paolo Carlini paolo.carl...@oracle.com
PR c++/51316
* g++.dg/cpp0x/alignof4.C: New.
Index: testsuite/g++.dg/cpp0x/alignof4.C
===
--- testsuite/g++.dg/cpp0x/alignof4.C (revision 0)
+++ testsuite/g++.dg/cpp0x/alignof4.C (revision 0)
@@ -0,0 +1,7 @@
+// PR c++/51316
+// { dg-options -std=c++0x }
+
+int main()
+{
+ alignof(int []);
+}
Index: c-family/c-common.c
===
--- c-family/c-common.c (revision 182710)
+++ c-family/c-common.c (working copy)
@@ -4382,13 +4382,22 @@ c_sizeof_or_alignof_type (location_t loc,
return error_mark_node;
value = size_one_node;
}
- else if (!COMPLETE_TYPE_P (type))
+ else if (!COMPLETE_TYPE_P (type)
+ (!c_dialect_cxx () || is_sizeof || type_code != ARRAY_TYPE))
{
if (complain)
- error_at (loc, invalid application of %qs to incomplete type %qT ,
+ error_at (loc, invalid application of %qs to incomplete type %qT,
op_name, type);
return error_mark_node;
}
+ else if (c_dialect_cxx () type_code == ARRAY_TYPE
+ !COMPLETE_TYPE_P (TREE_TYPE (type)))
+{
+ if (complain)
+ error_at (loc, invalid application of %qs to array type %qT of
+ incomplete element type, op_name, type);
+ return error_mark_node;
+}
else
{
if (is_sizeof)
