undefined reference to `log'

c math random makefile ld
Shade picture Shade · Feb 4, 2012 · Viewed 47k times · Source

I am trying to compile the implementation of the RFC 3797 random selection algorithm by Donald Eastlake (code: http://kambing.ui.ac.id/minix/other/rfc3797/). However, I am getting a linker error:

rfc3797.c:(.text+0xe7f): undefined reference to `log'

I am trying to make it with the provided Makefile, which explicitly links against the math libraray, but I still get the error:

cc -lm -o randomselection rfc3797.c MD5.c

How can I compile this program?

Answer

fajran picture fajran · Feb 4, 2012

I don't know what the reason is, but if you move -lm to the end, it will compile.

$ cc -o randomselection rfc3797.c MD5.c -lm
rfc3797.c: In function ‘getinteger’:
rfc3797.c:183:3: warning: format not a string literal and no format arguments [-Wformat-security]

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