Hi Arnaud, this is a great feature. How does it handle unchecked unions? Will
it warn if you write to a field but only read the value via a different field?
Ciao, Duncan.
GNAT did not issue a warning when assigning to a part of an object, and not
referencing the object later on. Now it does so in some cases, similarly to
the existing warnings on assignment to elementary objects.
On the code below, GNAT now issues warnings:
$ gcc -c -gnatwa assign.adb
assign.adb:8:05: warning: useless assignment to "X", value never referenced
assign.adb:9:04: warning: useless assignment to "Y", value never referenced
---
procedure Assign is
type T is record
U : Integer;
end record;
X : T := T'(U => 0);
Y : array (1..2) of Integer := (others => 0);
begin
X.U := X.U + 1;
Y (2) := Y (1);
end Assign;
Tested on x86_64-pc-linux-gnu, committed on trunk
2011-08-04 Yannick Moy<[email protected]>
* checks.adb (Apply_Float_Conversion_Check): correct a typo where Lo_OK
was used instead of Hi_OK, which could cause a read of an uninitialized
value later on. Detected while working on the new warning.
* exp_ch9.adb (Expand_N_Entry_Declaration): remove useless assignment
to local variable.
* sem_ch5.adb (Analyze_Assignment): set the last assignment component
in more cases, in order to detect more unreferenced values.
* sem_util.adb, sem_util.ads (Get_Enclosing_Object): return enclosing
object for expression, if any.
