对 `std::ios_base::Init::Init()' 的未定义引用

Question

I write this code to read 3 files, TM is the size of square matrix, LER the No. of rows of an array and from last value define a non-square matrix of (ler/2)*2

Then... the code read a file with some relations, all are numbers and are assign to C[ler].

Then ... C[ler] is assigned to B[ler/2][2].

Those coordinates, per row, in B[ler/2][2] are assign to a and b.

a and b are the row and the column of the matrix A[tm][tm] where to add 1.

My code crashes and I don't see what the error is.

When I try to compile it, the compiler gcc -g -o MatSim MatSim.cpp prompted:

/usr/include/c++/4.6/iostream:75: undefined reference to `std::ios_base::Init::Init()'
/usr/include/c++/4.6/iostream:75: undefined reference to `std::ios_base::Init::~Init()'
collect2: ld returned 1 exit status

Also, when I try to compile it, the compiler f77 -o MatSim MatSim.cpp prompted:

/tmp/cc6ewlkf.o: In function `__static_initialization_and_destruction_0(int, int)':
MatSim.cpp:(.text+0x17ad4a): undefined reference to `std::ios_base::Init::Init()'
MatSim.cpp:(.text+0x17ad4f): undefined reference to `std::ios_base::Init::~Init()'
collect2: ld returned 1 exit status

Solution

The main problem was a library problem, Compile your code using:

 g++ -g -o MatSim MatSim.cpp -lstdc

Still not working? Install libraries:

sudo apt-get install g++-multilib

Answer 1

You can resolve this in several ways:

• Use g++ in stead of gcc : g++ -g -o MatSim MatSim.cpp
• Add -lstdc++ : gcc -g -o MatSim MatSim.cpp -lstdc++
• Replace <string.h> by <string>

This is a linker problem, not a compiler issue. The same problem is covered in the question iostream linker error – it explains what is going on.

Answer 2

Most of these linker errors occur because of missing libraries.

I added the libstdc++.6.dylib in my Project->Targets->Build Phases-> Link Binary With Libraries.

That solved it for me on Xcode 6.3.2 for iOS 8.3

Cheers!

Answer 3

g++ is equivalent to gcc -xc++ -lstdc++ -shared-libgcc

I was getting a similar error while using sizeof() method. By using g++ or above tags with gcc, the code got compiled.