[COMMITTED 15/16] ada: String interpolation: report error without Extensions allowed

[Marc Poulhiès]

From: Javier Miranda <mira...@adacore.com>

The compiler does not report the correct error in occurrences
of interpolated strings, when the sources are compiled without
language extensions allowed.

gcc/ada/

        * scng.adb (Scan): Call Error_Msg_GNAT_Extension() to report an
        error, when the sources are compiled without Core_Extensions_
        Allowed, and the scanner detects the beginning of an interpolated
        string.

Tested on x86_64-pc-linux-gnu, committed on master.

---
 gcc/ada/scng.adb | 36 +++++++++++++++++++++++-------------
 1 file changed, 23 insertions(+), 13 deletions(-)

diff --git a/gcc/ada/scng.adb b/gcc/ada/scng.adb
index 08ce2ab5ad1..658970fbab2 100644
--- a/gcc/ada/scng.adb
+++ b/gcc/ada/scng.adb
@@ -2135,14 +2135,19 @@ package body Scng is
          --  Lower case letters
 
          when 'a' .. 'z' =>
-            if Core_Extensions_Allowed
-              and then Source (Scan_Ptr) = 'f'
+            if Source (Scan_Ptr) = 'f'
               and then Source (Scan_Ptr + 1) = '"'
             then
-               Scan_Ptr := Scan_Ptr + 1;
-               Accumulate_Checksum (Source (Scan_Ptr));
-               Token := Tok_Left_Interpolated_String;
-               return;
+               if Core_Extensions_Allowed then
+                  Scan_Ptr := Scan_Ptr + 1;
+                  Accumulate_Checksum (Source (Scan_Ptr));
+                  Token := Tok_Left_Interpolated_String;
+                  return;
+               else
+                  Error_Msg_GNAT_Extension
+                    ("interpolated string", Scan_Ptr,
+                     Is_Core_Extension => True);
+               end if;
             end if;
 
             Name_Len := 1;
@@ -2155,15 +2160,20 @@ package body Scng is
          --  Upper case letters
 
          when 'A' .. 'Z' =>
-            if Core_Extensions_Allowed
-              and then Source (Scan_Ptr) = 'F'
+            if Source (Scan_Ptr) = 'F'
               and then Source (Scan_Ptr + 1) = '"'
             then
-               Error_Msg_S
-                 ("delimiter of interpolated string must be in lowercase");
-               Scan_Ptr := Scan_Ptr + 1;
-               Token := Tok_Left_Interpolated_String;
-               return;
+               if Core_Extensions_Allowed then
+                  Error_Msg_S
+                    ("delimiter of interpolated string must be in lowercase");
+                  Scan_Ptr := Scan_Ptr + 1;
+                  Token := Tok_Left_Interpolated_String;
+                  return;
+               else
+                  Error_Msg_GNAT_Extension
+                    ("interpolated string", Scan_Ptr,
+                     Is_Core_Extension => True);
+               end if;
             end if;
 
             Token_Contains_Uppercase := True;
-- 
2.45.2