We hit the Constraint_Error because Start_Column is outside bounds. So
it should not be returned because that will again raise a
Constraint_Error. Instead return its type'Last which is then properly
handled.
Also reformat the Blanks_Loop to be a simple loop. It seems, the nested
if's were written for performance consideration. This does not seem do
be relevant anymore.
Tested on x86_64-pc-linux-gnu, committed on trunk
gcc/ada/
* scng.adb (Set_Start_Column): Return Column_Number'Last when
handling Constraint_Error. Plus reformat a strangely 7 level if
loop.diff --git a/gcc/ada/scng.adb b/gcc/ada/scng.adb
--- a/gcc/ada/scng.adb
+++ b/gcc/ada/scng.adb
@@ -2701,52 +2701,13 @@ package body Scng is
Tabs_Loop : loop
- -- Inner loop scans past blanks as fast as possible, bumping Scan_Ptr
- -- past the blanks and adjusting Start_Column to account for them.
-
- Blanks_Loop : loop
- if Source (Scan_Ptr) = ' ' then
- if Source (Scan_Ptr + 1) = ' ' then
- if Source (Scan_Ptr + 2) = ' ' then
- if Source (Scan_Ptr + 3) = ' ' then
- if Source (Scan_Ptr + 4) = ' ' then
- if Source (Scan_Ptr + 5) = ' ' then
- if Source (Scan_Ptr + 6) = ' ' then
- Scan_Ptr := Scan_Ptr + 7;
- Start_Column := Start_Column + 7;
- else
- Scan_Ptr := Scan_Ptr + 6;
- Start_Column := Start_Column + 6;
- exit Blanks_Loop;
- end if;
- else
- Scan_Ptr := Scan_Ptr + 5;
- Start_Column := Start_Column + 5;
- exit Blanks_Loop;
- end if;
- else
- Scan_Ptr := Scan_Ptr + 4;
- Start_Column := Start_Column + 4;
- exit Blanks_Loop;
- end if;
- else
- Scan_Ptr := Scan_Ptr + 3;
- Start_Column := Start_Column + 3;
- exit Blanks_Loop;
- end if;
- else
- Scan_Ptr := Scan_Ptr + 2;
- Start_Column := Start_Column + 2;
- exit Blanks_Loop;
- end if;
- else
- Scan_Ptr := Scan_Ptr + 1;
- Start_Column := Start_Column + 1;
- exit Blanks_Loop;
- end if;
- else
- exit Blanks_Loop;
- end if;
+ -- Inner loop scans past blanks, bumping Scan_Ptr past the blanks and
+ -- adjusting Start_Column to account for them.
+
+ Blanks_Loop :
+ while Source (Scan_Ptr) = ' ' loop
+ Scan_Ptr := Scan_Ptr + 1;
+ Start_Column := Start_Column + 1;
end loop Blanks_Loop;
-- Outer loop keeps going only if a horizontal tab follows
@@ -2771,7 +2732,7 @@ package body Scng is
exception
when Constraint_Error =>
- return Start_Column;
+ return Column_Number'Last;
end Set_Start_Column;
end Scng;
