#include using namespace std; template
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C ++ "new T [size]" not working?

I have a template class defined as:

#include <stdio.h>
#include <queue>

using namespace std;

template<class T>
class tbufferpool {
private:
    const int m_initial;
    const int m_size;
    const int m_total;
    T *m_buffer;
    vector<T*> m_queue;

public:
    // constructor
    tbufferpool(int initial, int size) : m_initial(initial), m_size(size), m_total(initial*size) {
        m_buffer = new T[m_total];
        T* next_buffer = m_buffer;
        for (int i = 0; i < initial; ++i, next_buffer += size) {
            m_queue.push_back(next_buffer);
        }
    }

and at some point in the constructor, I:

m_buffer = new T[size];

This works for most use cases, but in one test I get the following memory error indicated by valgrind (command and corresponding snippet below), however the test still passes fine. An interesting bit operator new(unsigned long)means that it does not highlight or align for a particular T type; I set the "double" setting, as I expected, but for unsigned long? If I change my implementation of bufferpool and hard-code new double[size], then this memory error is not displayed, but, of course, I only work with tbufferpool<double>.

, ? new T[size] ? , . ?

Test_matrix - , 30 . , valgrind, , . , new T[size] , new double[size]. AraxisMerge, . , , , ...?

$ valgrind --show-reachable=yes --dsymutil=yes --track-origins=yes ./test_matrix
  [snip]
  ==3719== Conditional jump or move depends on uninitialised value(s)
  ==3719==    at 0x3BE86C8: mkl_blas_dscal (in /opt/intel/composerxe-2011.4.184/mkl/lib/libmkl_mc3.dylib)
  ==3719==    by 0x432FFFFFFFFFFFFF: ???
  ==3719==  Uninitialised value was created by a heap allocation
  ==3719==    at 0xD62F: malloc (vg_replace_malloc.c:266)
  ==3719==    by 0x97B15C: operator new(unsigned long) (in /opt/local/lib/gcc46/libstdc++.6.dylib)
  ==3719==    by 0x7FFF5FBFE54F: ???
  ==3719==    by 0x10014BDBF: ???
  ==3719==    by 0x7FFF5FBFE58F: ???
  ==3719==    by 0x97B288: operator new[](unsigned long) (in /opt/local/lib/gcc46/libstdc++.6.dylib)
  ==3719==    by 0x7FFF5FBFE58F: ???
  ==3719==    by 0x100013853: tbufferpool<double>::tbufferpool(int, int) (bufferpool.h:30)
  ==3719==    by 0x7003FFFFF: ???
  ==3719==    by 0x100079E7F: ??? (in ./test_matrix)
  ==3719==    by 0x7FFF5FBFE58F: ???
  ==3719==    by 0x10014BE0F: ???
  ==3719== 
  ==3719== Conditional jump or move depends on uninitialised value(s)
  ==3719==    at 0x3BE86CA: mkl_blas_dscal (in /opt/intel/composerxe-2011.4.184/mkl/lib/libmkl_mc3.dylib)
  ==3719==    by 0x432FFFFFFFFFFFFF: ???
  ==3719==  Uninitialised value was created by a heap allocation
  ==3719==    at 0xD62F: malloc (vg_replace_malloc.c:266)
  ==3719==    by 0x97B15C: operator new(unsigned long) (in /opt/local/lib/gcc46/libstdc++.6.dylib)
  ==3719==    by 0x7FFF5FBFE54F: ???
  ==3719==    by 0x10014BDBF: ???
  ==3719==    by 0x7FFF5FBFE58F: ???
  ==3719==    by 0x97B288: operator new[](unsigned long) (in /opt/local/lib/gcc46/libstdc++.6.dylib)
  ==3719==    by 0x7FFF5FBFE58F: ???
  ==3719==    by 0x100013853: tbufferpool<double>::tbufferpool(int, int) (bufferpool.h:30)
  ==3719==    by 0x7003FFFFF: ???
  ==3719==    by 0x100079E7F: ??? (in ./test_matrix)
  ==3719==    by 0x7FFF5FBFE58F: ???
  ==3719==    by 0x10014BE0F: ???
  [snip]

:

/Users/bravegag/code/fastcode_project/build_debug$ uname -a && g++ --version
Darwin Macintosh-4.local 11.3.0 Darwin Kernel Version 11.3.0: Thu Jan 12 18:47:41 PST 2012; 
root:xnu-1699.24.23~1/RELEASE_X86_64 x86_64
g++ (GCC) 4.6.3
Copyright (C) 2011 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+5
2

m_buffer = new T[size];


m_buffer = new T[size]();

, valgrind:

Conditional jump or move depends on uninitialised value

, , valgrind . , , - blas, , BLAS .

+4

. Valgrind , , m_buffer.


T value;
// use value




T values[size];
// use values

, ,


m_buffer = new T[size];
std::fill_n(m_buffer, size, T());



m_buffer = new T[size](); // doesn't work in gcc3.x.x

std::vector.

+2

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