"undefined symbol: errno" while compiling under Sun Solaris 10 using Sun compiler.

I am trying to make this compile in Solaris 1o for SPARC using the Sun Studio 
compiler ver. 12  and i get the following error for 'errno'

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$ gmake
cc -g    -c -o main.o main.c
"main.c", line 272: warning: statement not reached
cc -g    -c -o iperf_api.o iperf_api.c
"iperf_api.c", line 805: warning: statement not reached
cc -g    -c -o iperf_server_api.o iperf_server_api.c
"iperf_server_api.c", line 179: warning: improper pointer/integer combination: o
"iperf_server_api.c", line 195: warning: improper pointer/integer combination: o
cc -g    -c -o iperf_tcp.o iperf_tcp.c
cc -g    -c -o iperf_udp.o iperf_udp.c
cc -g    -c -o timer.o timer.c
"timer.c", line 120: undefined symbol: errno
cc: acomp failed for timer.c
gmake: *** [timer.o] Error 1

$ CC -V
CC: Sun C++ 5.10 SunOS_sparc 128228-08 2010/04/21
Usage: CC [ options ] files.  Use 'CC -flags' for details
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Original issue reported on code.google.com by joe.vi...@gmail.com on 14 Jun 2010 at 2:58

yubin00145865 / iperf

"undefined symbol: errno" while compiling under Sun Solaris 10 using Sun compiler. #21