From 4dbdeeb889dfd4dcce214e1525b56a7464128a3c Mon Sep 17 00:00:00 2001 From: Steve Baird Date: Wed, 17 Feb 2021 17:54:53 -0800 Subject: [Ada] Avoid inappropriate error messages regarding aggregates and variant parts gcc/ada/ * sem_util.adb (Gather_Components): Factor the test that was already being used to govern emitting a pre-Ada_2020 error message into an expression function, OK_Scope_For_Discrim_Value_Error_Messages. Call that new function in two places: the point where the same test was being performed previously, and in governing emission of a newer Ada_2020 error message. In both cases, the out-mode parameter Gather_Components.Report_Errors is set to True even if no error messages are generated within Gather_Components. * sem_util.ads: Correct a comment. --- gcc/ada/sem_util.adb | 26 +++++++++++++++++++------- gcc/ada/sem_util.ads | 3 ++- 2 files changed, 21 insertions(+), 8 deletions(-) diff --git a/gcc/ada/sem_util.adb b/gcc/ada/sem_util.adb index 01690f3..73a6f79 100644 --- a/gcc/ada/sem_util.adb +++ b/gcc/ada/sem_util.adb @@ -9990,6 +9990,18 @@ package body Sem_Util is Discrim_Value : Node_Id; Discrim_Value_Subtype : Node_Id; Discrim_Value_Status : Discriminant_Value_Status := Bad; + + function OK_Scope_For_Discrim_Value_Error_Messages return Boolean is + (Scope (Original_Record_Component + (Entity (First (Choices (Assoc))))) = Typ); + -- Used to avoid generating error messages having a source position + -- which refers to somewhere (e.g., a discriminant value in a derived + -- tagged type declaration) unrelated to the offending construct. This + -- is required for correctness - clients of Gather_Components such as + -- Sem_Ch3.Create_Constrained_Components depend on this function + -- returning True while processing semantically correct examples; + -- generating an error message in this case would be wrong. + begin Report_Errors := False; @@ -10178,9 +10190,7 @@ package body Sem_Util is -- every value of that subtype (and there must be at least one) -- selects the same variant. - if Scope (Original_Record_Component - ((Entity (First (Choices (Assoc)))))) = Typ - then + if OK_Scope_For_Discrim_Value_Error_Messages then if Ada_Version >= Ada_2020 then Error_Msg_FE ("value for discriminant & must be static or " & @@ -10299,10 +10309,12 @@ package body Sem_Util is (Subset => Discrim_Value_Subtype_Intervals, Of_Set => Variant_Intervals) then - Error_Msg_NE - ("no single variant is associated with all values of " & - "the subtype of discriminant value &", - Discrim_Value, Discrim); + if OK_Scope_For_Discrim_Value_Error_Messages then + Error_Msg_NE + ("no single variant is associated with all values of " & + "the subtype of discriminant value &", + Discrim_Value, Discrim); + end if; Report_Errors := True; return; end if; diff --git a/gcc/ada/sem_util.ads b/gcc/ada/sem_util.ads index 83791fc..2e26c28 100644 --- a/gcc/ada/sem_util.ads +++ b/gcc/ada/sem_util.ads @@ -1079,7 +1079,8 @@ package Sem_Util is -- to its tail. -- -- Report_Errors is set to True if the values of the discriminants are - -- non-static. + -- insufficiently static (see body for details of what that means). + -- -- Allow_Compile_Time if set to True, allows compile time known values in -- Governed_By expressions in addition to static expressions. -- cgit v1.1