_DEFINE_FLEX(9)

✨ _DEFINE_FLEX(9) ✨

okay so real talk, this one's a kernel API manual page (section 9, we love a niche queen 👑) and it's lowkey the backstage helper for the whole DEFINE_FLEX() family. think of it as the plug behind the plug 💅

🎀 NAME 🎀

_DEFINE_FLEX — the helper macro for the DEFINE_FLEX() family. fr fr its whole job is letting the caller macro pass in a (different) initializer. that's it. that's the gig ✨

🦋 SYNOPSIS 🦋

_DEFINE_FLEX (type , name , member , count , initializer... );

yes bestie, that trailing ... is doing heavy lifting, we'll get to it 🌸

💖 ARGUMENTS 💖

• type — the structure type name, and yes it's gotta include the struct keyword. don't forget it, she's picky 🫶
• name — the name for the variable you're defining. literally what you're gonna be typing everywhere afterwards.
• member — the name of the array member. the flexible one, the main character 🌈
• count — how many elements are in the array. must be compile-time const, no cap, this is not negotiable 😭
• initializer — the initializer expression. minimum viable is passing = { }, like, at least that much please 🙈

🔥 SEE ALSO 🔥

all of these live over in the kernel file ./include/linux/overflow.h — go say hi to the whole overflow family, they're all icons:

• check_add_overflow(9)
• wrapping_add(9)
• wrapping_assign_add(9)
• check_sub_overflow(9)
• wrapping_sub(9)
• wrapping_assign_sub(9)
• check_mul_overflow(9)
• wrapping_mul(9)
• check_shl_overflow(9)
• overflows_type(9)
• range_overflows(9)
• range_overflows_t(9)
• range_end_overflows(9)
• range_end_overflows_t(9)
• castable_to_type(9)
• size_mul(9)
• size_add(9)
• size_sub(9)
• array_size(9)
• array3_size(9)
• flex_array_size(9)
• struct_size(9)
• struct_size_t(9)
• struct_offset(9)
• __DEFINE_FLEX(9)
• DEFINE_RAW_FLEX(9)
• DEFINE_FLEX(9)
• STACK_FLEX_ARRAY_SIZE(9)
• typeof_flex_counter(9)
• overflows_flex_counter_type(9)
• __set_flex_counter(9)

💜 that's the whole page bestie, go be flexible (in the struct way). this came out of ./include/linux, it's Kernel API Manual business, and the date on the tin is October 2026 — mwah, stan kernel docs 🎀✨🦋