C baseline for ACO TSP

In my previous post on the Multi-Core Problem I discussed comparing the performance of multi-core-friendly languages to the baseline performance of single-threaded C code. The test case I have been using is Ant Colony Optimization for TSP. In a recent post Leonardo Maffi has rewritten my ACO TSP code in C. This provides a baseline for comparisons:

           Time   Multiple   Speedup    
        in secs       of C    (1->2)          
C           0.4          1       n/a
Scala      10.0         25       1.7
Haskell    22.0         55       1.4
Erlang     93.0        233       1.9

gcc (GCC) 4.2.4 (Debian 4.2.4-1).
Compiled gcc -Wall -O3 -s ant_c.c -o ant_c
Still 1000 iterations, 200 cities.
Times for other languages from here .
Initial speedups from here (Scala interpolated), and do not model decay at higher numbers of cores.