On Wednesday, 17 July 2024 at 17:24:15 UTC, IchorDev wrote:

char[] s;
printf("%s\n", s);

So does copying a D array, but that is safe.

Responding to your post in DIP development here (because that's for reviews):

pragma(msg, printf) printf(const char* fmt, ...) @safe;

What the above would mean is that printf is @safe only when fmt is given a string literal. String literals are guaranteed to be zero-terminated, so there's no assumption of that here. If the pragma checks are not met, printf is actually treated as @system.

That requires modification for this proposal. It is true when given a char* for the format parameter. But when a string literal implicitly converts to char*, it has a safe interface due to the pragma, because the literal is statically allocated and is never accessed past its allocation when called from @safe code.

On Thursday, 18 July 2024 at 16:45:02 UTC, Nick Treleaven wrote:

pragma(msg, printf) printf(const char* fmt, ...) @safe;

I messed that up:

pragma(printf) extern(C) int printf(const char* fmt, ...) @safe;