Gcc/10.2.0/gcc/C 002dSKY-Function-Attributes

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6.33.9 C-SKY Function Attributes

These function attributes are supported by the C-SKY back end:

interrupt
isr

Use these attributes to indicate that the specified function is an interrupt handler. The compiler generates function entry and exit sequences suitable for use in an interrupt handler when either of these attributes are present.

Use of these options requires the -mistack command-line option to enable support for the necessary interrupt stack instructions. They are ignored with a warning otherwise. See C-SKY Options.

naked

This attribute allows the compiler to construct the requisite function declaration, while allowing the body of the function to be assembly code. The specified function will not have prologue/epilogue sequences generated by the compiler. Only basic asm statements can safely be included in naked functions (see Basic Asm). While using extended asm or a mixture of basic asm and C code may appear to work, they cannot be depended upon to work reliably and are not supported.