memory leak in _solve_iml(self, Matrix_integer_dense B, right=True) #514
Description
Hello,
I got the following leak while looking at #454 further:
==9632== 3,416,000 (2,196,032 direct, 1,219,968 indirect) bytes in 110 blocks are definitely lost in loss record 2,823 of 2,
824
==9632== at 0x4A05809: malloc (vg_replace_malloc.c:149)
==9632== by 0x203196F8: __pyx_f_20matrix_integer_dense_20Matrix_integer_dense__solve_iml (matrix_integer_dense.c:13639)
==9632== by 0x4156A2: PyObject_Call (abstract.c:1860)
==9632== by 0x47DB71: PyEval_CallObjectWithKeywords (ceval.c:3433)
==9632== by 0x203018C0: __pyx_f_20matrix_integer_dense_20Matrix_integer_dense__rational_echelon_via_solve (matrix_integer
_dense.c:14916)
==9632== by 0x4156A2: PyObject_Call (abstract.c:1860)
==9632== by 0x47DB71: PyEval_CallObjectWithKeywords (ceval.c:3433)
==9632== by 0x20BA375D: __pyx_f_21matrix_rational_dense_21Matrix_rational_dense__echelon_form_padic (matrix_rational_dens
e.c:8784)
==9632== by 0x4156A2: PyObject_Call (abstract.c:1860)
==9632== by 0x47DB71: PyEval_CallObjectWithKeywords (ceval.c:3433)
==9632== by 0x20B7D01B: __pyx_f_21matrix_rational_dense_21Matrix_rational_dense_echelon_form (matrix_rational_dense.c:852
3)
==9632== by 0x485A8A: PyEval_EvalFrameEx (ceval.c:3564)
The problem starts at line 1857 of sage/matrix/matrix_integer_dense.pyx:
if m == 0 or n == 0:
return self.new_matrix(nrows = n, ncols = m), Integer(1)
mp_N = <mpz_t *> sage_malloc( n * m * sizeof(mpz_t) ) [line 1857]
for i from 0 <= i < n * m:
mpz_init( mp_N[i] )
Then after the computation has finished we try to deallocate in line 1884, specifically line 1887:
M = Matrix_integer_dense.__new__(Matrix_integer_dense, P, None, None, None)
for i from 0 <= i < n*m:
mpz_init_set(M._entries[i], mp_N[i])
mpz_clear(mp_N[i]) [line 1887]
M._initialized = True
The code certainly looks correct, but somehow things do go wrong. I don't like the look of "<mpz_t*> sage_alloc" Any ideas?
Cheers,
Michael
Component: basic arithmetic
Issue created by migration from https://trac.sagemath.org/ticket/514