fix alignment of fields within mqoi_desc_t - #5
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…d when interpreting as uint32_t
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It is better to use the following method: typedef struct {
uint8_t head;
uint8_t magic[4]; __attribute__((aligned(4)));
uint8_t width[4] __attribute__((aligned(4))); // big-endian width
uint8_t height[4] __attribute__((aligned(4))); // big-endian height
uint8_t channels;
uint8_t colorspace;
} mqoi_desc_t;Then the compiler will apply 4-byte alignment inside the |
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Attempting to use the minimal code example on an RP2040 fails (the board crashes) while attempting to run mqoi_desc_verify.
I narrowed the crash down to the line https://github.com/shraiwi/mini-qoi/blob/master/src/mini_qoi.c#L34, which casts a potentially unaligned uint8_t* to a uint32_t*, which is undefined behavior. Padding the struct so the width/height fields are 4-byte aligned fixes the issue.