using std::find linking fail in linux

I am trying to experiment <algorithm>'s find to search for an item in a
vector of struct. My bit of test code is shown below.

Code:

#include <algorithm>
#include <iterator>
#include <functional>

bool operator==( const ClsInstBk& rhs, const ClsInstBk& lhs );

class	ClsInstBkTable
{
public:
	ClsInstBkTable();
	UINT32 Add( const ClsInstBk& breakpoint );	// Add a breakpoint
	UINT32 Remove( const ClsInstBk& breakpoint ); // Remove a breakpoint
	bool IsBreak( UINT32 ulPC );	//check if the specified PC is breakpoint or not
	UINT32 ClearAll();		//clear all breakpoints
	bool IsBreakInstruction( TypMemoryData ulValue );
	int Find( UINT32 ulPC );//return -1 if ulPC is not set  breakpoint, else return index of pool
	TypMemoryData GetOriginalMemoryValue( int index );
	UINT32 EnableBreak( UINT32 index );
	int DisableBreak( UINT32 index );
	static TypMemoryData BreakInstruction;
private:
	vector<ClsInstBk>	_vecBkTable;
};

......

UINT32 ClsInstBkTable::Add( const ClsInstBk& temp )
{
	//if breakpoint is not in table, add it; 
	//std::vector<ClsInstBk>::iterator i = std::find( _vecBkTable.begin(), _vecBkTable.end(), temp );
	std::vector<ClsInstBk>::iterator i;
	i = std::find( _vecBkTable.begin(), _vecBkTable.end(), temp );
	if( _vecBkTable.end() == i )
	{
		_vecBkTable.push_back( temp );
	}
	return 0;
}

The compile is ok. But the link is fail and errors as following.

Code:

g++ -g -Wno-deprecated -DGEN_MIF -DNO_DPI -I/localhome/tools/systemc-2.2.0/include -I/home/tools/NC_Verilog/IUS6.2/linux/tools/include/ -I. -I./../../include ./breakpoint.o ./eDSP_decode_grab.o ./eDSP_decode.o ./eDSP_cmd.o ./eDSP_disasmoneinst.o ./eDSP_grab.o ./eDSP_hardware.o ./eDSP_misc.o ./main.o  -L/localhome/tools/systemc-2.2.0/lib-linux -L/usr/lib -lm -lsystemc -lpthread -o eDSP
./breakpoint.o(.gnu.linkonce.t._ZSt4findIN9__gnu_cxx17__normal_iteratorIP9ClsInstBkSt6vectorIS2_SaIS2_EEEES2_ET_S8_S8_RKT0_St26random_access_iterator_tag+0x3d): In function `__gnu_cxx::__normal_iterator<ClsInstBk*, std::vector<ClsInstBk, std::allocator<ClsInstBk> > > std::find<__gnu_cxx::__normal_iterator<ClsInstBk*, std::vector<ClsInstBk, std::allocator<ClsInstBk> > >, ClsInstBk>(__gnu_cxx::__normal_iterator<ClsInstBk*, std::vector<ClsInstBk, std::allocator<ClsInstBk> > >, __gnu_cxx::__normal_iterator<ClsInstBk*, std::vector<ClsInstBk, std::allocator<ClsInstBk> > >, ClsInstBk const&, std::random_access_iterator_tag)':
/usr/lib/gcc/i386-redhat-linux/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:207: undefined reference to `operator==(ClsInstBk const&, ClsInstBk const&)'
./breakpoint.o(.gnu.linkonce.t._ZSt4findIN9__gnu_cxx17__normal_iteratorIP9ClsInstBkSt6vectorIS2_SaIS2_EEEES2_ET_S8_S8_RKT0_St26random_access_iterator_tag+0x78):/usr/lib/gcc/i386-redhat-linux/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:211: undefined reference to `operator==(ClsInstBk const&, ClsInstBk const&)'

./breakpoint.o(.gnu.linkonce.t._ZSt4findIN9__gnu_cxx17__normal_iteratorIP9ClsInstBkSt6vectorIS2_SaIS2_EEEES2_ET_S8_S8_RKT0_St26random_access_iterator_tag+0xb3):/usr/lib/gcc/i386-redhat-linux/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:215: undefined reference to `operator==(ClsInstBk const&, ClsInstBk const&)'

./breakpoint.o(.gnu.linkonce.t._ZSt4findIN9__gnu_cxx17__normal_iteratorIP9ClsInstBkSt6vectorIS2_SaIS2_EEEES2_ET_S8_S8_RKT0_St26random_access_iterator_tag+0xee):/usr/lib/gcc/i386-redhat-linux/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:219: undefined reference to `operator==(ClsInstBk const&, ClsInstBk const&)'

./breakpoint.o(.gnu.linkonce.t._ZSt4findIN9__gnu_cxx17__normal_iteratorIP9ClsInstBkSt6vectorIS2_SaIS2_EEEES2_ET_S8_S8_RKT0_St26random_access_iterator_tag+0x16f):/usr/lib/gcc/i386-redhat-linux/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:227: undefined reference to `operator==(ClsInstBk const&, ClsInstBk const&)'

./breakpoint.o(.gnu.linkonce.t._ZSt4findIN9__gnu_cxx17__normal_iteratorIP9ClsInstBkSt6vectorIS2_SaIS2_EEEES2_ET_S8_S8_RKT0_St26random_access_iterator_tag+0x1aa):/usr/lib/gcc/i386-redhat-linux/3.4.6/../../../../include/c++/3.4.6/bits/stl_algo.h:231: more undefined references to `operator==(ClsInstBk const&, ClsInstBk const&)' follow
collect2: ld returned 1 exit status

I don't fully understand what the error message is trying to say.

Any comments appreciated.

The error message seems to be saying that the linker cannot find the implementation of this

Code:

bool operator==( const ClsInstBk& rhs, const ClsInstBk& lhs );

Either you don't have the implementation, or you are not compiling and linking it.

Originally Posted by anon

The error message seems to be saying that the linker cannot find the implementation of this

Code:

bool operator==( const ClsInstBk& rhs, const ClsInstBk& lhs );

Either you don't have the implementation, or you are not compiling and linking it.

Thank you. Yes, it does. After adding the implementation of operator==, it's ok.