--- On Thu, 6/9/11, Brian Budge <brian.budge@xxxxxxxxx> wrote: > From: Brian Budge <brian.budge@xxxxxxxxx> > Subject: Re: undefined reference, plz help > To: "eric lin" <ericlin@xxxxxxxxxxxxx> > Cc: gcc-help@xxxxxxxxxxx > Date: Thursday, June 9, 2011, 8:52 AM > On Wed, Jun 8, 2011 at 9:26 PM, eric > lin <ericlin@xxxxxxxxxxxxx> > wrote: > > > > Dear gcc programers: > > > > what may cause compile error (on 4.5.2 or maybe > not) > > ------ > > g++ pg49.cpp > > /tmp/ccUvNoPf.o: In function `main': > > pg49.cpp:(.text+0x42): undefined reference to > `IntArray::IntArray(int*, int)' > > pg49.cpp:(.text+0x5e): undefined reference to > `IntArrayRC::IntArrayRC(int*, int)' > > /tmp/ccUvNoPf.o: In function `IntArray::~IntArray()': > > > pg49.cpp:(.text._ZN8IntArrayD2Ev[_ZN8IntArrayD5Ev]+0xb): > undefined reference to `vtable for IntArray' > > /tmp/ccUvNoPf.o: In function > `IntArrayRC::~IntArrayRC()': > > > pg49.cpp:(.text._ZN10IntArrayRCD2Ev[_ZN10IntArrayRCD5Ev]+0xb): > undefined reference to `vtable for IntArrayRC' > > collect2: ld returned 1 exit status > > -------- > > eric /* I am happy to supply code I compiled, plz > show up your private email address or email me privately */ > > > > > > > > > > This means that you've declared, but not defined those > constructors. > At link time, the linker cannot find the code for those > functions. > > Brian > Just a small correction: these are destructors or other virtual functions that are undefined, not constructors. HTH -Pavel
