On 8/15/22 10:03, Richard Biener wrote:
On Mon, Aug 15, 2022 at 3:29 PM Nathan Sidwell via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
On 8/2/22 10:44, Qing Zhao wrote:
Hi, Nathan,
I am adding a new bitfield “decl_not_flexarray” in “tree_decl_common”
(gcc/tree-core.h) for the new gcc feature -fstrict-flex-arrays.
====
diff --git a/gcc/tree-core.h b/gcc/tree-core.h
index ea9f281f1cc..458c6e6ceea 100644
--- a/gcc/tree-core.h
+++ b/gcc/tree-core.h
@@ -1813,7 +1813,10 @@ struct GTY(()) tree_decl_common {
TYPE_WARN_IF_NOT_ALIGN. */
unsigned int warn_if_not_align : 6;
- /* 14 bits unused. */
+ /* In FIELD_DECL, this is DECL_NOT_FLEXARRAY. */
+ unsigned int decl_not_flexarray : 1;
Is it possible to invert the meaning here -- set the flag if it /IS/ a
flexible array? negated flags can be confusing, and I see your patch
sets it to '!is_flexible_array (...)' anyway?
The issue is it's consumed by the middle-end but set by a single (or two)
frontends and the conservative setting is having the bit not set. That works
nicely together with touching just the frontends that want stricter behavior
than currently ...
Makes sense, but is the comment incomplete? I'm guessing this flag is
for FIELD_DECLs /of array type/, and not just any old FIELD_DECL? After
all a field of type int is not a flexible array, but presumably doesn't
need this flag setting?
nathan
--
Nathan Sidwell
