[Ada] Crash on expression functions within quantified expressions

[Pierre-Marie de Rodat <derodat at adacore dot com>]

This patch fixes an issue whereby using a call to an expression function
as the domain of iteration for a loop would trigger a crash due to the
function not being frozen appropriately.

Tested on x86_64-pc-linux-gnu, committed on trunk

2018-09-26  Justin Squirek  <squirek@adacore.com>

gcc/ada/

	* sem_ch5.adb (Analyze_Iterator_Specification): Add conditional
	to freeze called functions within iterator specifications during
	full analysis.
	(Preanalyze_Range): Minor typo fix.

gcc/testsuite/

	* gnat.dg/expr_func8.adb: New testcase.

--- gcc/ada/sem_ch5.adb
+++ gcc/ada/sem_ch5.adb
@@ -2203,6 +2203,19 @@ package body Sem_Ch5 is
 
       Preanalyze_Range (Iter_Name);
 
+      --  If the domain of iteration is a function call, make sure the function
+      --  itself is frozen. This is an issue if this is a local expression
+      --  function.
+
+      if Nkind (Iter_Name) = N_Function_Call
+        and then Is_Entity_Name (Name (Iter_Name))
+        and then Full_Analysis
+        and then (In_Assertion_Expr = 0
+                   or else Assertions_Enabled)
+      then
+         Freeze_Before (N, Entity (Name (Iter_Name)));
+      end if;
+
       --  Set the kind of the loop variable, which is not visible within the
       --  iterator name.
 
@@ -4136,10 +4149,10 @@ package body Sem_Ch5 is
       Full_Analysis := False;
       Expander_Mode_Save_And_Set (False);
 
-      --  In addition to the above we must ecplicity suppress the
-      --  generation of freeze nodes which might otherwise be generated
-      --  during resolution of the range (e.g. if given by an attribute
-      --  that will freeze its prefix).
+      --  In addition to the above we must explicitly suppress the generation
+      --  of freeze nodes that might otherwise be generated during resolution
+      --  of the range (e.g. if given by an attribute that will freeze its
+      --  prefix).
 
       Set_Must_Not_Freeze (R_Copy);
 

--- /dev/null
new file mode 100644
+++ gcc/testsuite/gnat.dg/expr_func8.adb
@@ -0,0 +1,37 @@
+--  { dg-do compile }
+--  { dg-options "-gnata" }
+
+procedure Expr_Func8 is
+
+   type Node_Set is array (Positive range <>) of Integer;
+
+   function Nodes return Node_Set is
+     ((1,2,3,4,5,6,7,8,9));
+
+   X1 : Boolean := (for all N of Nodes => N = N);
+
+   function Predecessors (N : Integer) return Node_Set Is
+      (Nodes (1 .. N - 1));
+   function Successors (N : Integer) return Node_Set Is
+      (Nodes (N + 1 .. Nodes'Last));
+
+   pragma Assert
+     (for all N of Nodes =>
+       (for some S of Successors (N) => S = N));
+
+   X2 : Boolean :=
+     (for all N of Nodes =>
+       (for some S of Successors (N) => S = N));
+
+   X3 : Boolean :=
+     (for all N of Nodes =>
+       (for some S of Successors (N) => S = N)) with Ghost;
+
+   pragma Assert
+      (for all N of Nodes =>
+      (for all P of Predecessors (N) =>
+      (for some S of Successors (P) => S = N)));
+
+begin
+   null;
+end;