problem with GCC 4.3.1

[iceb0y]

i switched to linux11 from 10.2.before i havnt any problem with gcc 4.2 for compiling my packages but now i have problem with gcc 4.3.1.the problem is with some commands and std that i have in my code.i wanna know how can i switch to gcc 4.2 or how can i fix this problem?

[Atom]

Please give the error message that you get.

[iceb0y]

g++ -DNDEBUG -I../librescue -c -o main.o main.cc
In file included from ../librescue/connection_manager.h:20,
from main.cc:18:
../librescue/udp.h: In member function ‘void Librescue::LongUDPConnection::Fragment::fill(Libre scue::INT_16, Librescue::INT_16, Librescue::INT_16, Librescue::Byte*, int)’:
../librescue/udp.h:54: error: ‘memcpy’ was not declared in this scope
main.cc: In function ‘void addNewObject(Librescue::Config&, Librescue::ObjectPool&, Librescue::RescueObject*)’:
main.cc:63: error: ‘srand’ was not declared in this scope
main.cc:68: error: ‘rand’ was not declared in this scope
main.cc: In function ‘Librescue::INT_32 readInt(FILE*)’:
main.cc:84: error: ‘exit’ was not declared in this scope
main.cc:86: error: ‘exit’ was not declared in this scope
main.cc:88: error: ‘exit’ was not declared in this scope
main.cc:90: error: ‘exit’ was not declared in this scope
main.cc: In function ‘void readRoads(Librescue::Config&, Librescue::ObjectPool&)’:
main.cc:194: error: ‘exit’ was not declared in this scope
main.cc: In function ‘void readNodes(Librescue::Config&, Librescue::ObjectPool&)’:
main.cc:230: error: ‘exit’ was not declared in this scope
main.cc: In function ‘void readBuildings(Librescue::Config&, Librescue::ObjectPool&)’:
main.cc:282: error: ‘exit’ was not declared in this scope
main.cc: In function ‘void readGisini(Librescue::Config&, Librescue::ObjectPool&)’:
main.cc:362: error: ‘exit’ was not declared in this scope
main.cc:420: error: ‘exit’ was not declared in this scope
main.cc: In function ‘void replaceBuilding(Librescue::INT_32, Librescue::Building*, Librescue::ObjectPool&)’:
main.cc:432: error: ‘exit’ was not declared in this scope
make: *** [main.o] Error 1

but in gcc 4.2 i never face these errors!!
what is wrong?
and in other code i have seen the error to std:: scope