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Altera_Forum
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13 years ago

Problems with installing Nios2 Linux

I am attempting to install the Nios2 Linux development tools on a Centos 6.3 based system. I am somewhat confused by the instructions (on alteras wiki: Install_Nios_II_Linux). They indicate tha...
Altera_Forum's avatar
Altera_Forum
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8 years ago

Hi,

--- Quote Start ---

Thanks. It compiles now until the next bug:

kernel/built-in.o(.text+0x2ea40): In function `get_update_sysctl_factor':
: undefined reference to `____ilog2_NaN'
kernel/built-in.o(.text+0x2ea40): In function `get_update_sysctl_factor':
: relocation truncated to fit: R_NIOS2_CALL26 ____ilog2_NaN
make: ***  Error 1
make: ***  Error 2
make: Leaving directory `/home/developer/altera/nios2-linux/linux-2.6'
make: ***  Error 1

--- Quote End ---

This is a long term bug which is caused by using the compiler optimization algorithm. ____ilog2_NaN is inserted to check the sanity of variable, and this function is eliminated during the optimization in normal situations, so the kernal will not call it actually. But it seems that they have finally given up this doubtful method.

http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1340693.html

So, please try to delete the function ____ilog2_NaN from the file 'include/linux/log2.h' according to the diff contents which is written in the last part of its mail.

Kazu