The internal packages used to implement Ada.Text_IO.Float_IO declare
some String variables that need to be large enough to hold the longest
possible images computed by Float_IO. If Exp is specified to be zero and
Aft is specified to be Text_IO.Field'Last then the computed image of
Long_Long_Float'Last requires slightly less than 5200 characters.
Change the bounds of these String variables so that they are large
enough to support this case.
Tested on x86_64-pc-linux-gnu, committed on trunk
2020-06-04 Steve Baird <ba...@adacore.com>
gcc/ada/
* libgnat/s-imgrea.ads: Declare a named number
Max_Real_Image_Length with value 5200. Provide a comment
explaining why this value was chosen.
* libgnat/s-imgrea.adb (Set_Image_Real): Increase the upper
bound of the local String variable Digs to
Max_Real_Image_Length.
* libgnat/a-tiflau.adb (Put): Increase the upper bound of the
local String variable Buf to Max_Real_Image_Length.
(Puts): Increase the upper bound of the local String variable
Buf to Max_Real_Image_Length.--- gcc/ada/libgnat/a-tiflau.adb
+++ gcc/ada/libgnat/a-tiflau.adb
@@ -194,7 +194,7 @@ package body Ada.Text_IO.Float_Aux is
Aft : Field;
Exp : Field)
is
- Buf : String (1 .. 3 * Field'Last + 2);
+ Buf : String (1 .. Max_Real_Image_Length);
Ptr : Natural := 0;
begin
@@ -212,7 +212,7 @@ package body Ada.Text_IO.Float_Aux is
Aft : Field;
Exp : Field)
is
- Buf : String (1 .. 3 * Field'Last + 2);
+ Buf : String (1 .. Max_Real_Image_Length);
Ptr : Natural := 0;
begin
--- gcc/ada/libgnat/s-imgrea.adb
+++ gcc/ada/libgnat/s-imgrea.adb
@@ -151,14 +151,9 @@ package body System.Img_Real is
Scale : Integer;
Expon : Integer;
- Field_Max : constant := 255;
- -- This should be the same value as Ada.[Wide_]Text_IO.Field'Last.
- -- It is not worth dragging in Ada.Text_IO to pick up this value,
- -- since it really should never be necessary to change it.
-
- Digs : String (1 .. 2 * Field_Max + 16);
- -- Array used to hold digits of converted integer value. This is a
- -- large enough buffer to accommodate ludicrous values of Fore and Aft.
+ Digs : String (1 .. Max_Real_Image_Length);
+ -- Array used to hold digits of converted integer value. This is a large
+ -- enough buffer to accommodate ludicrous Fore/Aft/Exp combinations.
Ndigs : Natural;
-- Number of digits stored in Digs (and also subscript of last digit)
--- gcc/ada/libgnat/s-imgrea.ads
+++ gcc/ada/libgnat/s-imgrea.ads
@@ -73,4 +73,9 @@ package System.Img_Real is
-- can be set to any valid values for the case of use from Text_IO. Note
-- that no space is stored at the start for non-negative values.
+ Max_Real_Image_Length : constant := 5200;
+ -- If Exp is set to zero and Aft is set to Text_IO.Field'Last (i.e., 255)
+ -- then Long_Long_Float'Last generates an image whose length is
+ -- slightly less than 5200.
+
end System.Img_Real;
