[Ada] Avoid internal compiler error for illegal Predicate_Failure aspect spec

gcc/ada/

	* sem_ch13.adb (Build_Predicate_Functions): If a semantic error
	has been detected then ignore Predicate_Failure aspect
	specifications in the same way as is done for CodePeer and
	SPARK. This avoids an internal compiler error if
	Ancestor_Predicate_Function_Called is True but Result_Expr is
	not an N_And_Then node (and is therefore unsuitable as an
	argument in a call to Left_Opnd).

diff --git a/gcc/ada/sem_ch13.adb b/gcc/ada/sem_ch13.adb
index c405d15..11abdd8 100644 (file)
--- a/gcc/ada/sem_ch13.adb
+++ b/gcc/ada/sem_ch13.adb
@@ -10489,11 +10489,14 @@ package body Sem_Ch13 is
             begin
                --  In GNATprove mode we are only interested in the predicate
                --  expression itself and don't want a raise expression that
-               --  comes from the Predicate_Failure.
+               --  comes from the Predicate_Failure. Ditto for CodePeer.
+               --  And an illegal Predicate_Failure aspect can lead to cases
+               --  we want to avoid.
 
                if Present (PF_Expr)
                  and then not GNATprove_Mode
                  and then not CodePeer_Mode
+                 and then Serious_Errors_Detected = 0
                then
                   pragma Assert (Present (Second_Formal));