On Thu, 3 Apr 2014, Theodore Ts'o wrote: > fs/mbcache.c: doucple the locking of local from global data
This change causes breakage: fs/built-in.o: In function `__mb_cache_entry_release': mbcache.c:(.text+0x56b3c): undefined reference to `log2' mbcache.c:(.text+0x56b3c): relocation truncated to fit: R_MIPS_26 against `log2' mbcache.c:(.text+0x56b74): undefined reference to `__fixunsdfsi' mbcache.c:(.text+0x56b74): relocation truncated to fit: R_MIPS_26 against `__fixunsdfsi' mbcache.c:(.text+0x56be4): undefined reference to `log2' mbcache.c:(.text+0x56be4): relocation truncated to fit: R_MIPS_26 against `log2' mbcache.c:(.text+0x56bf0): undefined reference to `__fixunsdfsi' mbcache.c:(.text+0x56bf0): relocation truncated to fit: R_MIPS_26 against `__fixunsdfsi' and so on, and so on. It uses __builtin_log2() that is a floating-point function, its corresponding <math.h> prototype is: -- Function: double log2 (double X) (GCC builtins are of course implicitly prototyped). Please note that floating-point calculations are not allowed in the kernel and relying on the compiler to optimise them away is risky to say the least. Can you please rewrite the fragment using __builtin_log2() so as to avoid the floating-point calculation, using ffs() or suchlike perhaps? Maciej -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
