[gcc r12-3730] [Ada] Simplify iteration when printing error message spans

[Pierre-Marie de Rodat]

https://gcc.gnu.org/g:255279b91ecc1872539f469453b6cb05ccb75b37

commit r12-3730-g255279b91ecc1872539f469453b6cb05ccb75b37
Author: Piotr Trojanek <trojanek@adacore.com>
Date:   Thu Jul 1 15:40:00 2021 +0200

    [Ada] Simplify iteration when printing error message spans
    
    gcc/ada/
    
            * errout.adb (Write_Source_Code_Lines): Use Cur_Loc before
            incrementing it, so that we don't need to decrement it.

Diff:
---
 gcc/ada/errout.adb | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/gcc/ada/errout.adb b/gcc/ada/errout.adb
index c859d8c5110..0b10d41181b 100644
--- a/gcc/ada/errout.adb
+++ b/gcc/ada/errout.adb
@@ -2693,9 +2693,7 @@ package body Errout is
                      Write_Buffer_Char (Buf, Cur_Loc);
                   end if;
 
-                  Cur_Loc := Cur_Loc + 1;
-
-                  if Buf (Cur_Loc - 1) = ASCII.LF then
+                  if Buf (Cur_Loc) = ASCII.LF then
                      Cur_Line := Cur_Line + 1;
 
                      --  Output ... for skipped lines
@@ -2720,6 +2718,8 @@ package body Errout is
                            Width);
                      end if;
                   end if;
+
+                  Cur_Loc := Cur_Loc + 1;
                end loop;
             end;