17 May
2011
17 May
'11
2:32 p.m.
Dear Aneesh V,
In message 4DD2657F.3020708@ti.com you wrote:
+struct ch_toc {
- uint32_t section_offset;
- uint32_t section_size;
- uint8_t unused[12];
- uint8_t section_name[12];
+} __attribute__ ((__packed__));
+struct ch_settings {
- uint32_t section_key;
- uint8_t valid;
- uint8_t version;
- uint16_t reserved;
- uint32_t flags;
+} __attribute__ ((__packed__));
+struct gp_header {
- uint32_t size;
- uint32_t load_addr;
+} __attribute__ ((__packed__));
...
No. Not in the structs listed above.
Why do you think it will not create any problems. For instance, what if the field "uint8_t version" in "struct ch_settings" is aligned to a 32 bit boundary by the compiler for faster access? That is not the intended layout.
If the compiler did such a thing, this would indeed be bad. But I have never seen a compiler doing this, nor is there a reason to do so. The naturla alignment requirement for a uint8_t is a byte; ther eis no need to align it on 4 byte boundary.
Best regards,
Wolfgang Denk
--
DENX Software Engineering GmbH, MD: Wolfgang Denk & Detlev Zundel
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Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
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