https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61632
--- Comment #16 from Dominique d'Humieres <dominiq at lps dot ens.fr> ---
> This:
>
> + fmt->format_string_len = strrchr (f->source, ')') - f->source + 1;
>
>Is taking the difference between two string pointers, ie memory addresses
>
> This:
>
> printf("pos 0 =%x, pos ) =%x\n",strchr (f->source, '\0'),strrchr (f->source,
> ')'));
>
> Is printing the value of the pointers, the addresses.
>
> Are you expecting something different?
Well, I am fully aware that I am C challenged (the kind who can forget two
semicolons while writing a single line!). However the above is more or less
part of what I understand.
To clarify my question, let me summarize what I understand:
(1) This PR occurs iff 'f != NULL',
(2) The beginning of f->source is the unprocessed part of the format when the
error occurs, the last character of it being the closing ')' of the format,
(3) while I was expecting f->source being
unprocessed_part\0garbage
I have examples for which I see
unprocessed_partxxx\0garbage
where xxx are some extra characters (from 1 to ~15). My question was about the
origin of these characters.
Indeed I was not happy with 'strrchr (f->source, ')')' because it could find a
')' in the garbage after '\0'. In addition, valgrind complained about it.
I have regtested and ran my own tests with the following change
if (f != NULL)
- fmt->format_string = f->source;
+ {
+ width = strlen (f->source);
+ for (i = width - 1; i > 0; i--)
+ {
+ if (f->source[i] == ')')
+ break;
+ width--;
+ }
+ fmt->format_string_len = width;
+ }
This makes valgrind happy without regression (I know that this will fail if the
extra characters contain a ')', so far I did not crossed this situation).
