Printing long long in C

Question

I'm working on a program that convert strings to integers. The code works just fine but I got this warning that I can't solve. I tried to look it up but nothing helpful was found.

Here is the simple code:

#include <stdio.h>

int main() {
    char x[8] = "ABCDWXYZ";
    long long sum = 0;

    for (int i = 0; i < 8; i++) {
        sum = sum * 100 + (long long)x[i];
    }
    printf("%lli", sum);

    return 0;
}

Here's the warning I got:

too many arguments for format [-Wformat-extra-args]  //Line 11
unknown conversion type character 'l' in format [-Wformat=]  //Line 11

Also, different strings will cover to the same integer with your program, as there's actually more possible `char` outside the range (0,99) than inside it. — Marcus Müller, Apr 12 '23 at 07:25
`char x[8] = "ABCDWXYZ"` -> `char x[9] = "ABCDWXYZ"` or even better `char x[] = "ABCDWXYZ"` — Jabberwocky, Apr 12 '23 at 07:46
@Jabberwocky I don't see how will that change anything. anyway I tried it and as expected it multiplied the result *100 once more. — Alex, Apr 12 '23 at 07:52
@Alex That version is half decade (2018) old, try using MSYS2 instead — Darth-CodeX, Apr 12 '23 at 08:04
@Darth-CodeX I'm not allowed to make any changes in the in company's computers — Alex, Apr 12 '23 at 08:07
@Alex, I tried running your above code in mingw 6.2 it DID NOT produced any warning — Darth-CodeX, Apr 12 '23 at 08:10
@Darth-CodeX Well, Let's just pray it doesn't show up on my boss's computer. :) — Alex, Apr 12 '23 at 08:22
@alex just tell him its computers fault not yours, show him this online compiler https://godbolt.org/z/f4f5bvx4z — Darth-CodeX, Apr 12 '23 at 08:30
@alex Is your real goal to sort strings (as per comment below)? In that case I fail to see the idea of converting to integers. — nielsen, Apr 12 '23 at 09:03
@Jabberwocky `char x[8] = "ABCDWXYZ";` is fine as long as `x` isn't used as a string — Support Ukraine, Apr 12 '23 at 09:07
Related https://stackoverflow.com/questions/52201952/warning-on-64bit-string-formatter-in-mingw-environment — Support Ukraine, Apr 12 '23 at 09:15
Related https://sourceforge.net/p/mingw-w64/wiki2/gnu%20printf/ — Support Ukraine, Apr 12 '23 at 09:23
Also duplicate here: https://stackoverflow.com/q/70593571/584518 (I won't dupe hammer with my own answers as target since I'm partial) — Lundin, Apr 12 '23 at 09:36

chux - Reinstate Monica · Answer 1 · 2023-04-12T12:55:21.397

1

Compiler, mingw v 6.2, with the compiler options used do not understand the "ll", in "%lli".

Alternatives.

Compile as C11. @Haris
Use a more up-to-date compiler. (OP implies this is not an option.)
Re-code and use some crafted helper function to output a 64-bit as decimal text.
Re-code and use compiler specific formats. Not reccomendeded.

OP's sum * 100 + (long long)x[i] is curious. To read 8 characters of an 8 character array and form all possible 64-bit values, I'd expect unsigned long long sum, sum * (UCHAR_MAX+1) + (unsigned char)x[i] and "%llu". That magic number 100 seems strange. Maybe OP meant 0x100?

edited Apr 12 '23 at 12:55

answered Apr 12 '23 at 12:43

chux - Reinstate Monica

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I don't see why compiling as C11 would make any difference since the problem is non-conformance with C99. This whole thing is a known bug in Mingw + libs and the work-around is `#define __USE_MINGW_ANSI_STDIO 1` before including stdio.h. – Lundin Apr 12 '23 at 13:14

Printing long long in C

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