# gcc alantop.cpp
/tmp/cchoAlDx.o: In function `__static_initialization_and_destruction_0(int, int )':
alantop.cpp:(.text+0x38): undefined reference to `std::ios_base::Init::Init()'
alantop.cpp:(.text+0x3d): undefined reference to `std::ios_base::Init::~Init()'
/tmp/cchoAlDx.o:(.eh_frame+0x12): undefined reference to `__gxx_personality_v0'
collect2: ld returned 1 exit status
增加編譯參數 -lstdc++
# gcc alantop.cpp -lstdc++