On 01/19/2014 05:30 PM, Antonio Quartulli wrote: > On 19/01/14 02:10, James Hogan wrote: >> >> It appears that the following gcc patch adds support for #pragma pack: >> http://gcc.gnu.org/ml/gcc-patches/2006-10/msg01115.html >> >> I gave it a quick spin on metag gcc (which is unfortunately stuck on an old >> version) and it seems to fix my simple test case so that #pragma pack(2) >> becomes equivalent to __packed __aligned(2) (for sizeof and __alignof__). >> > > Then I personally think that it is better to fix metag gcc instead of > changing the kernel. > > Actually there are many different spots where "#pragma pack" is used. > batman-adv is just the only one having compile time checks for structure > sizes. > What Antonio said sounds reasonable to me. >> >> However, the __packed and __aligned are linux specific macros to abstract >> compiler details, whereas #pragma pack appears to be a compiler-specific WIN32 >> style equivalent to GCC's __attribute__((packed)) and >> __attribute__((aligned(2))) (these are what __packed and __aligned use in >> compiler-gcc.h). >> >> Therefore I believe using the Linux abstractions is still more correct here. > > If you really think so, I'd suggest to grep in the kernel and catch all > the other occurrences of "#pragma pack" and change them all (assuming > that using __attribute__((aligned(2))) is the way to go). > Thanks. -- Chen Gang Open, share and attitude like air, water and life which God blessed -- To unsubscribe from this list: send the line "unsubscribe linux-metag" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
