Hey, I had a weird problem using GiNaC with g++-4.8. It seems that GiNac::symbol will be deleted twice if it's not dynamically declared. In other words, some resources in it is free'd before the automatic destructor is called when the scope finishes. The minimum code to re-produce the issue is: #include <ginac/ginac.h> int main() { GiNaC::symbol x("x"); return 0; } $ g++-4.8 -g -o main main0.cc -lginac -lcln && ./main main(69018) malloc: *** error for object 0x7fff73275570: pointer being freed was not allocated It seems this issue only exists in g++-4.8. g++-4.7 is fine. I briefly looked at symbol.h but did not manage to locate the problem. I was hoping someone here more familiar with the code base could fix it or provide some direction for me. Thanks. -- Song Gao http://song.gao.io/