https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85651
Martin Sebor <msebor at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2018-05-07
CC| |msebor at gcc dot gnu.org
Component|c++ |tree-optimization
Ever confirmed|0 |1
--- Comment #2 from Martin Sebor <msebor at gcc dot gnu.org> ---
Confirmed. The warning is issued from gimple-ssa-warn-restrict.c for the
following expression:
_68 = &logBuilder + _69;
The offset _69 is in the anti-range ~[-9223372036854775800,
-9223372036854775800] which the warning pass interprets as/transforms into
[-9223372036854775799, -9223372036854775801] (this is the range referenced by
the diagnostic). The builtin_memref::offset_out_of_bounds() function detects
this kind of range and has special code to deal with it but only for references
of ARRAY_TYPE. In the test case, logBuilder is RECORD_TYPE so the special
handling isn't performed. The following lightly tested change adds this
handling for structs as well to avoid the spurious warning.
Index: gcc/gimple-ssa-warn-restrict.c
===================================================================
--- gcc/gimple-ssa-warn-restrict.c (revision 260013)
+++ gcc/gimple-ssa-warn-restrict.c (working copy)
@@ -475,7 +475,10 @@ builtin_memref::offset_out_of_bounds (int strict,
/* A temporary, possibly adjusted, copy of the offset range. */
offset_int offrng[2] = { offrange[0], offrange[1] };
- if (DECL_P (base) && TREE_CODE (TREE_TYPE (base)) == ARRAY_TYPE)
+ tree_code basecode = TREE_CODE (TREE_TYPE (base));
+ if (DECL_P (base)
+ && (basecode == ARRAY_TYPE
+ || basecode == RECORD_TYPE))
{
/* Check for offset in an anti-range with a negative lower bound.
For such a range, consider only the non-negative subrange. */
