Drop I length modifier from snprintf as it is unused

[Girgias]

Basing myself from the results of: https://gist.github.com/Girgias/b9a2b9926190630d433c84da0ef1b002 which indicate that the I (capital i) length modifier is unused, moreover it's not a C99 length modifier.

[Girgias]

Test failures unrelated

[nikic]

I believe these are there for Windows compatibility. Just to confirm @cmb69, these modifiers are no longer used if people use standard PRIu64 and friends?

[cmb69]

Well, I don't see any Windows specific problem with removing support for that modifier, but wouldn't that possibly affect external extensions?

[Girgias]

Well, I don't see any Windows specific problem with removing support for that modifier, but wouldn't that possibly affect external extensions?

Well as all internal changes it could affect external extensions but shouldn't those be using the relevant macros, instead of the I modifier.

[cmb69]

@Girgias yes, they should use the macros; I don't know if they do, though.

[Girgias]

@Girgias yes, they should use the macros; I don't know if they do, though.

Meh, could always provide the grep regex so people can check but this is one of the discrepancies with the standard snprintf function. So I wouldn't expect that many people to use an unofficial one. But maybe need to check PECL extensions?

[cmb69]

@Girgias, thinking about it, that shouldn't be a real issue for a major version (if documented).

[Girgias]

@Girgias, thinking about it, that shouldn't be a real issue for a major version (if documented).

Adding a note to UPGRADING.INTERNALS seemed obvious, not sure how I should formulate it however, maybe provide a link to the relevant macros? (which I'm not exactly sure where they are located)

[cmb69]

which I'm not exactly sure where they are located

php-src/Zend/zend_long.h

Lines 57 to 61 in 691880b

	# define ZEND_LONG_FMT "%" PRId64
	# define ZEND_ULONG_FMT "%" PRIu64
	# define ZEND_XLONG_FMT "%" PRIx64
	# define ZEND_LONG_FMT_SPEC PRId64
	# define ZEND_ULONG_FMT_SPEC PRIu64

[Girgias]

which I'm not exactly sure where they are located

php-src/Zend/zend_long.h

Lines 57 to 61 in 691880b

	# define ZEND_LONG_FMT "%" PRId64
	# define ZEND_ULONG_FMT "%" PRIu64
	# define ZEND_XLONG_FMT "%" PRIx64
	# define ZEND_LONG_FMT_SPEC PRId64
	# define ZEND_ULONG_FMT_SPEC PRIu64

Thanks, so no objections for me to merge this with a note in UPGRADING.INTERNALS?