10.2.5 Data Memory Allocation Macros

The sys/attribs.h header file provides many macros for commonly used attributes in order to enhance code readability.

`__section__(s)`	Apply the `section` attribute with section name `s`.
`__unique_section__`	Apply the `unique_section` attribute.
`__ramfunc__`	Locate the attributed function in the RAM function code section.
`__longramfunc__`	Locate the attributed function in the RAM function code section and apply the `longcall` attribute.
`__longcall__`	Apply the `longcall` attribute.
`__ISR(v,ipl)`	Apply the `interrupt` attribute with priority level `ipl` and the `vector` attribute with vector number `v`.
`__ISR_AT_VECTOR(v,ipl)`	Apply the interrupt attribute with priority level `ipl` and the `at_vector` attribute with vector number `v`. This macro is especially useful on PIC32 devices that feature variable vector offsets.
`__ISR_SINGLE__`	Specifies a function as an Interrupt Service Routine in single-vector mode. This places a jump at the single-vector location to the interrupt handler.
`__ISR_SINGLE_AT_VECTOR__`	Places the entire single-vector interrupt handler at the vector 0 location. When used, ensure that the vector spacing is set to accommodate the size of the handler.