ada: Fix asymmetry in resolution of unary intrinsic operators

Resolution of binary and unary intrinsic operators differed when
expansion was inactive. In particular, this affected GNATprove
handling of Ada.Real_Time."abs" operator. This patch makes unary
resolution behave like binary resolution.

gcc/ada/ChangeLog:

	* sem_res.adb (Resolve_Intrinsic_Unary_Operator): Disable when
	expansion is inactive.

1 files changed, 7 insertions, 0 deletions

diff --git a/gcc/ada/sem_res.adb b/gcc/ada/sem_res.adb
index 6a2680b..0abdeee 100644
--- a/gcc/ada/sem_res.adb
+++ b/gcc/ada/sem_res.adb
@@ -9972,6 +9972,13 @@ package body Sem_Res is
       Arg2 : Node_Id;
 
    begin
+      --  We must preserve the original entity in a generic setting, so that
+      --  the legality of the operation can be verified in an instance.
+
+      if not Expander_Active then
+         return;
+      end if;
+
       Op := Entity (N);
       while Scope (Op) /= Standard_Standard loop
          Op := Homonym (Op);