Comment 3 for bug 1740426

Mark, you're right, MSVC supports %z for size_t (which is certainly preferred over the Microsoft-specific %I). This is supported at least since VS 2015 (https://docs.microsoft.com/en-us/cpp/c-runtime-library/format-specification-syntax-printf-and-wprintf-functions?view=vs-2015#size-prefixes-for-printf-and-wprintf-format-type-specifiers). But I'm not aware of a sane portable way of writing

int64_t i = 42;
printf("Works on Windows only: %I64d\n", i);

other than

printf("Works on all C99-compatible platforms: %"PRId64"\n", i);

Sure the following works

printf("Works on all C99-compatible platforms: %lli\n", (long long)i);

but I always have to pull up the standard to be sure the type I'm casting to has sufficient size on all platforms. And it also requires C99.