This patch fixes a spurious error in a generic unit that invludes a
subtype with a static predicate, when the type is used in a case
expression.
Tested on x86_64-pc-linux-gnu, committed on trunk
2019-07-03 Ed Schonberg <schonb...@adacore.com>
gcc/ada/
* sem_ch13.adb (Build_Predicate_Functions): In a generic context
we do not build the bodies of predicate fuctions, but the
expression in a static predicate must be elaborated to allow
case coverage checking within the generic unit.
(Build_Discrete_Static_Predicate): In a generic context, return
without building function body once the
Static_Discrete_Predicate expression for the type has been
constructed.
gcc/testsuite/
* gnat.dg/predicate6.adb, gnat.dg/predicate6.ads: New testcase.
* gnat.dg/static_pred1.adb: Remove expected error.--- gcc/ada/sem_ch13.adb
+++ gcc/ada/sem_ch13.adb
@@ -8201,6 +8201,13 @@ package body Sem_Ch13 is
Set_Static_Discrete_Predicate (Typ, Plist);
+ -- Within a generic the predicate functions themselves need not
+ -- be constructed.
+
+ if Inside_A_Generic then
+ return;
+ end if;
+
-- The processing for static predicates put the expression into
-- canonical form as a series of ranges. It also eliminated
-- duplicates and collapsed and combined ranges. We might as well
@@ -8733,9 +8740,13 @@ package body Sem_Ch13 is
-- Do not generate predicate bodies within a generic unit. The
-- expressions have been analyzed already, and the bodies play
- -- no role if not within an executable unit.
+ -- no role if not within an executable unit. However, if a statc
+ -- predicate is present it must be processed for legality checks
+ -- such as case coverage in an expression.
- elsif Inside_A_Generic then
+ elsif Inside_A_Generic
+ and then not Has_Static_Predicate_Aspect (Typ)
+ then
return;
end if;
--- /dev/null
new file mode 100644
+++ gcc/testsuite/gnat.dg/predicate6.adb
@@ -0,0 +1,5 @@
+-- { dg-do compile }
+
+package body Predicate6 is
+ procedure Foo is null;
+end Predicate6;
--- /dev/null
new file mode 100644
+++ gcc/testsuite/gnat.dg/predicate6.ads
@@ -0,0 +1,10 @@
+generic
+package Predicate6 is
+ type Price_Kind is (Infinitely_Small, Normal, Infinitely_Large);
+ subtype Infinite_Kind is Price_Kind with Static_Predicate =>
+ Infinite_Kind in Infinitely_Small | Infinitely_Large;
+ function "not" (Kind : Infinite_Kind) return Infinite_Kind is
+ (case Kind is when Infinitely_Small => Infinitely_Large,
+ when Infinitely_Large => Infinitely_Small);
+ procedure Foo;
+end;
--- gcc/testsuite/gnat.dg/static_pred1.adb
+++ gcc/testsuite/gnat.dg/static_pred1.adb
@@ -8,7 +8,7 @@ package body Static_Pred1 is
Enum_Subrange in A | C;
function "not" (Kind : Enum_Subrange) return Enum_Subrange is
- (case Kind is -- { dg-error "missing case value: \"B\"" }
+ (case Kind is
when A => C,
when C => A);
