npendleton

  is_leap_year_fast:
        imul    eax, edi, 1073750999
        and     eax, -1073614833
        cmp     eax, 126977
        setb    al
        ret

  is_leap_year_fast:
        ldr     r1, .LCPI0_0
        mul     r0, r0, r1
        ldr     r1, .LCPI0_1
        and     r1, r0, r1
        mov     r0, #0
        cmp     r1, #126976
        movwls  r0, #1
        bx      lr
  .LCPI0_0:
        .long   1073750999
  .LCPI0_1:
        .long   3221352463

  - uses a pure software interrupt and redirects to your ISR's, so you incur additional overhead for all interrupts in your system
  - ships with a homegrown c stdlib, which has several functional/security bugs (ex: vscanf will overflow if you use format specifiers other than [l]i/u), and neglects to provide gcc attributes for arg checking for the printf family functions
  - build system issues $(MAKE) calls in every folder you're building, which makes it terrifically slow (especially noticeable on incremental builds)
  - architecture makes it difficult to write custom drivers without building them into the kernel (eg if you want to use the kernel as a module in your project)