From df61c5dc3a16178834651d3437da6fa4490b480b Mon Sep 17 00:00:00 2001 From: Gary Dismukes Date: Thu, 31 Mar 2022 16:33:01 -0400 Subject: [PATCH] [Ada] Overriding error on type derived from discriminated untagged private type When a derived type DT has an untagged private parent type PT with a discriminant, where the full type of PT is tagged, and DT inherits a function F with an anonymous access result that designates the type, the compiler wrongly reports an error saying that DT must be declared abstract or F overridden. A test is added to exclude checking the abstract overriding rules that should only apply to inherited subprograms of tagged derived types. gcc/ada/ * sem_ch3.adb (Check_Abstract_Overriding): If the type is derived from an untagged type, then don't perform any of the abstract overriding error checks. --- gcc/ada/sem_ch3.adb | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/gcc/ada/sem_ch3.adb b/gcc/ada/sem_ch3.adb index d41e271..dfade0f 100644 --- a/gcc/ada/sem_ch3.adb +++ b/gcc/ada/sem_ch3.adb @@ -11047,6 +11047,14 @@ package body Sem_Ch3 is Subp := Node (Elmt); Alias_Subp := Alias (Subp); + -- If the parent type is untagged, then no overriding error checks + -- are needed (such as in the case of an implicit full type for + -- a derived type whose parent is an untagged private type with + -- a tagged full type). + + if not Is_Tagged_Type (Etype (T)) then + null; + -- Inherited subprograms are identified by the fact that they do not -- come from source, and the associated source location is the -- location of the first subtype of the derived type. @@ -11065,7 +11073,7 @@ package body Sem_Ch3 is -- overriding in Ada 2005, but wrappers need to be built for them -- (see exp_ch3, Build_Controlling_Function_Wrappers). - if Is_Null_Extension (T) + elsif Is_Null_Extension (T) and then Has_Controlling_Result (Subp) and then Ada_Version >= Ada_2005 and then Present (Alias_Subp) -- 2.7.4