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AR# 14448

MicroBlaze - mb-gcc error message: "In function 'write': undefined reference to 'outbyte'"/"In function 'read': undefined reference to 'inbyte'"


General Description:

When I compile C-code, the following error message occurs:

"/xygdrive/d/MicroBlaze//lib/libc.a(write.o): In function `write':

write.o(.text+0x30): undefined reference to `outbyte'

write.o(.text+0x48): undefined reference to `outbyte'

/xygdrive/d/MicroBlaze//lib/libc.a(read.o): In function `read':

read.o(.text+0x38): undefined reference to `inbyte'"


This error occurs when the C-code contains "printf-" statements and a peripheral has not been defined as "std_out" and "std_in". To work around this problem, use one of the following solutions:

Remove the "printf-" statement.


Define peripheral as Standard-out and Standard-in.

This can be done by using the Software Platform Settings dialog box.
AR# 14448
Date Created 08/29/2007
Last Updated 09/02/2011
Status Archive
Type General Article