In the case described on this ticket, a predefined unit (the body of
Ada.Finalization) is recompiled with a configuration pragma in effect
(an Interrupt_State pragma) which has has the effect of introducing a
circular compilation dependency. Previously this resulted in an
internal error. With this change, a better error message is produced.
Tested on x86_64-pc-linux-gnu, committed on trunk
2019-12-12 Steve Baird <ba...@adacore.com>
gcc/ada/
* sem_ch10.adb (Install_With_Clause): Check for the case of a
circular dependency involving a predefined (or GNAT-defined)
unit and handle that case by generating an appropropriate error
message.--- gcc/ada/sem_ch10.adb
+++ gcc/ada/sem_ch10.adb
@@ -5336,6 +5336,20 @@ package body Sem_Ch10 is
Error_Msg_N
("instantiation depends on itself", Name (With_Clause));
+ elsif not Analyzed (Uname)
+ and then Is_Internal_Unit (Current_Sem_Unit)
+ and then not Is_Visible_Lib_Unit (Uname)
+ and then No (Scope (Uname))
+ then
+ if Is_Predefined_Unit (Current_Sem_Unit) then
+ Error_Msg_N
+ ("predefined unit depends on itself", Name (With_Clause));
+ else
+ Error_Msg_N
+ ("GNAT-defined unit depends on itself", Name (With_Clause));
+ end if;
+ return;
+
elsif not Is_Visible_Lib_Unit (Uname) then
-- Abandon processing in case of previous errors
