[COMMITTED] ada: Fix for validity checks combined with aliasing checks
Checks
Commit Message
From: Justin Squirek <squirek@adacore.com>
Attribute Overlaps_Storage, which can appear implicitly in expansion of
aliasing checks, is now excluded from operand validity checks. Likewise
for attribute Has_Same_Storage.
gcc/ada/
* exp_attr.adb (Expand_N_Attribute_Reference): Skip operand
validity checks for attributes Has_Same_Storage and
Overlaps_Storage.
Tested on x86_64-pc-linux-gnu, committed on master.
---
gcc/ada/exp_attr.adb | 16 +++++++++++-----
1 file changed, 11 insertions(+), 5 deletions(-)
@@ -1998,16 +1998,22 @@ package body Exp_Attr is
-- Start of processing for Expand_N_Attribute_Reference
begin
- -- Do required validity checking, if enabled. Do not apply check to
- -- output parameters of an Asm instruction, since the value of this
- -- is not set till after the attribute has been elaborated, and do
- -- not apply the check to the arguments of a 'Read or 'Input attribute
- -- reference since the scalar argument is an OUT scalar.
+ -- Do required validity checking, if enabled.
+ --
+ -- Skip check for output parameters of an Asm instruction (since their
+ -- valuesare not set till after the attribute has been elaborated),
+ -- for the arguments of a 'Read or 'Input attribute reference (since
+ -- the scalar argument is an OUT scalar) and for the arguments of a
+ -- 'Has_Same_Storage or 'Overlaps_Storage attribute reference (which not
+ -- considered to be reads of their prefixes and expressions, see Ada RM
+ -- 13.3(73.10/3)).
if Validity_Checks_On and then Validity_Check_Operands
and then Id /= Attribute_Asm_Output
and then Id /= Attribute_Read
and then Id /= Attribute_Input
+ and then Id /= Attribute_Has_Same_Storage
+ and then Id /= Attribute_Overlaps_Storage
then
declare
Expr : Node_Id;