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by maccard 1245 days ago
You're not always printing to a terminal,

    char buf[10];
    const char* foo = "wrong?";
    int res = snprintf(buf, 20, "What could possibly go %d", foo);
Will compile and do... something...
1 comments
jholine 1245 days ago
Solved problem since ages ago.

error: format '%d' expects argument of type 'int', but argument 4 has type 'const char*' [-Werror=format=]

You only get into trouble when you use runtime format strings (like passing a user string as first argument to printf)

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maccard 1244 days ago
That doesn't work on MSVC, and ignores multiple other issues with the 3 lines of code I shared (and as you correctly identified doesn't work with runtime format strings.

It also doesn't work if your code isn't a textbook example of being wrong. [0] is _slightly_ more contrived but still suffers all of the exact same problems, despite all of the information being available at compile time.

[0] https://gcc.godbolt.org/z/9vK3W4bYh

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