# uname -a
Linux hostname 2.6.18.xs4.0.1.900.5799 #2 SMP Mon Aug 13 13:56:47 UTC 2007 i686 GNU/Linux
# bzr checkout lp:tcprstat
# cd tcprstat/
# sh bootstrap
# ./configure
# make
[...]
gcc -DHAVE_CONFIG_H -I. -I.. -Wall -Werror -g -pthread -I../libpcap/libpcap-1.1.1/ -g -O2 -MT tcprstat-stats-hash.o -MD -MP -MF .deps/tcprstat-stats-hash.Tpo -c -o tcprstat-stats-hash.o `test -f 'stats-hash.c' || echo './'`stats-hash.c
stats-hash.c:297:2: error: #error Cannot determine sizeof(unsigned long)
make[2]: *** [tcprstat-stats-hash.o] Error 1
# grep -r SIZEOF_UNSIGNED_LONG .
./configure:#define SIZEOF_UNSIGNED_LONG $ac_cv_sizeof_unsigned_long
./config.status:s,^\([ #]*\)[^ ]*\([ ]*SIZEOF_UNSIGNED_LONG\)[ (].*,\1define\2 4 ,
./config.h:#define SIZEOF_UNSIGNED_LONG 4
./config.h.in:#undef SIZEOF_UNSIGNED_LONG
./config.log:#define SIZEOF_UNSIGNED_LONG 4
./autom4te.cache/traces.1:m4trace:configure.ac:50: -1- AC_DEFINE_TRACE_LITERAL([SIZEOF_UNSIGNED_LONG])
./autom4te.cache/traces.1:m4trace:configure.ac:50: -1- m4_pattern_allow([^SIZEOF_UNSIGNED_LONG$])
./autom4te.cache/traces.1:m4trace:configure.ac:50: -1- AH_OUTPUT([SIZEOF_UNSIGNED_LONG], [/* The size of `unsigned long\', as computed by sizeof. */
./autom4te.cache/traces.1:#undef SIZEOF_UNSIGNED_LONG])
./autom4te.cache/output.1:@%:@define SIZEOF_UNSIGNED_LONG $ac_cv_sizeof_unsigned_long
./autom4te.cache/output.0:@%:@define SIZEOF_UNSIGNED_LONG $ac_cv_sizeof_unsigned_long
./autom4te.cache/traces.0:m4trace:configure.ac:50: -1- m4_pattern_allow([^SIZEOF_UNSIGNED_LONG$])
./src/stats-hash.c:#if SIZEOF_UNSIGNED_LONG >= 8
There is a minor typo in the src/stats-hash.c file, here it is the patch that fixes it, Hope that helps