Documentation/coding style suggestion....

[rew]

On http://chibios.org/dokuwiki/doku.php?id ... _dma_guide I see:

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#if defined(__GNUC__)
__attribute__((aligned (32)))
#endif
static uint8_t txbuf[SPI_BUFFERS_SIZE];

Might I suggest to write such things as:

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ALIGNED32 static uint8_t txbuf[SPI_BUFFERS_SIZE];

and have

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#if defined(__GNUC__)
#define ALIGNED32 __attribute__((aligned (32)))
#else
// Auch! Data that needs 32-byte alignment will not be aligned! 
#warning "don't know how to align data to 32 bytes!"
#define ALIGNED32
#endif

somewhere else?

Why? First it deals with the compiler issue in one place. Adding a different compiler is easier when this is concentrated somewhere. Second it makes the code shorter and more readable. The code now clearly shows that the buffer needs 32-byte alignment, even if there is no way to indicate this to the compiler.

[Giovanni]

Probably the HAL should include a compiler-related abstraction module in order to implement that.

The problem are the dumb proprietary compilers that do not necessarily allow alignments, or implement them in a way that is not placeable in a macro like that.

Giovanni