[AstroPy] Curious bug in Pywcs?

Wed Sep 7 10:21:51 EDT 2011

It's a helpful data point that some backends work while others don't, 
but frustratingly, I am still unable to reproduce this myself using the 
Qt4Agg or GtkAgg backends.

Can you send the full valgrind log to me (off-list)?  There's nothing 
particularly special about the last entries -- it's more than likely the 
memory corruption occurs earlier than that.

Mike

On 09/07/2011 04:19 AM, Nicolas Gaudin wrote:
> Thank you for your tests.
>
> I was at home, with packages from debian testing (python 2.6 and
> matplotlib-1.0.1-3) and I reproduce the bug. I use Qt4Agg. Indeed, GTKAgg
> reproduces the bug but Agg and TkAgg don't. So, I will switch to another
> backend.
>
> The output of Valgrind is verbose, I will print only the last lines. I've used
> the option --leak-check=full.
>
> For a working backend (TkAgg):
>
> [...]
> ==15463== 786,432 bytes in 3 blocks are still reachable in loss record 2,167
> of 2,169
> ==15463==    at 0x4025018: malloc (in /usr/lib/valgrind/vgpreload_memcheck-
> x86-linux.so)
> ==15463==    by 0x8096176: PyObject_Malloc (in /usr/bin/python2.6)
> ==15463==    by 0x809652F: PyObject_Realloc (in /usr/bin/python2.6)
> ==15463==    by 0x8157AA4: PyNode_AddChild (in /usr/bin/python2.6)
> ==15463==    by 0x8157EBE: PyParser_AddToken (in /usr/bin/python2.6)
> ==15463==    by 0x805E81E: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80FAE9E: PyParser_ASTFromFile (in /usr/bin/python2.6)
> ==15463==    by 0x80F0321: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F1520: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F179F: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F1D75: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x8269003: ??? (in /usr/bin/python2.6)
> ==15463==
> ==15463== 786,432 bytes in 3 blocks are still reachable in loss record 2,168
> of 2,169
> ==15463==    at 0x4025018: malloc (in /usr/lib/valgrind/vgpreload_memcheck-
> x86-linux.so)
> ==15463==    by 0x8096176: PyObject_Malloc (in /usr/bin/python2.6)
> ==15463==    by 0x805E7CA: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80FAE9E: PyParser_ASTFromFile (in /usr/bin/python2.6)
> ==15463==    by 0x80F0321: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F1520: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F179F: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F1D75: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x8269003: ??? (in /usr/bin/python2.6)
> ==15463==
> ==15463== 1,048,576 bytes in 4 blocks are still reachable in loss record 2,169
> of 2,169
> ==15463==    at 0x4025018: malloc (in /usr/lib/valgrind/vgpreload_memcheck-
> x86-linux.so)
> ==15463==    by 0x8096176: PyObject_Malloc (in /usr/bin/python2.6)
> ==15463==    by 0x8157AA4: PyNode_AddChild (in /usr/bin/python2.6)
> ==15463==    by 0x8157EBE: PyParser_AddToken (in /usr/bin/python2.6)
> ==15463==    by 0x805E81E: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80FAE9E: PyParser_ASTFromFile (in /usr/bin/python2.6)
> ==15463==    by 0x80F0321: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F1520: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F179F: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x80F1D75: ??? (in /usr/bin/python2.6)
> ==15463==    by 0x8269003: ??? (in /usr/bin/python2.6)
> ==15463==
> ==15463== LEAK SUMMARY:
> ==15463==    definitely lost: 772 bytes in 10 blocks
> ==15463==    indirectly lost: 860 bytes in 46 blocks
> ==15463==      possibly lost: 1,524,749 bytes in 676 blocks
> ==15463==    still reachable: 11,457,411 bytes in 9,550 blocks
> ==15463==         suppressed: 0 bytes in 0 blocks
> ==15463==
> ==15463== For counts of detected and suppressed errors, rerun with: -v
> ==15463== Use --track-origins=yes to see where uninitialised values come from
> ==15463== ERROR SUMMARY: 13488 errors from 605 contexts (suppressed: 266 from
> 12)
>
> And with Qt4Agg:
>
> [...]
> ==15478== 786,432 bytes in 3 blocks are still reachable in loss record 2,585
> of 2,588
> ==15478==    at 0x4025018: malloc (in /usr/lib/valgrind/vgpreload_memcheck-
> x86-linux.so)
> ==15478==    by 0x8096176: PyObject_Malloc (in /usr/bin/python2.6)
> ==15478==    by 0x805E7CA: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x80FAE9E: PyParser_ASTFromFile (in /usr/bin/python2.6)
> ==15478==    by 0x80F0321: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x80F1520: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x80F179F: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x80F1D75: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x8269003: ??? (in /usr/bin/python2.6)
> ==15478==
> ==15478== 1,001,096 bytes in 1 blocks are possibly lost in loss record 2,586
> of 2,588
> ==15478==    at 0x4024604: operator new[](unsigned int) (in
> /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
> ==15478==    by 0x7FED313: RendererAgg::RendererAgg(unsigned int, unsigned
> int, double, int) (in
> /usr/lib/pyshared/python2.6/matplotlib/backends/_backend_agg.so)
> ==15478==    by 0x3801573F: ??? (in /usr/lib/valgrind/memcheck-x86-linux)
> ==15478==
> ==15478== 1,048,576 bytes in 4 blocks are still reachable in loss record 2,587
> of 2,588
> ==15478==    at 0x4025018: malloc (in /usr/lib/valgrind/vgpreload_memcheck-
> x86-linux.so)
> ==15478==    by 0x8096176: PyObject_Malloc (in /usr/bin/python2.6)
> ==15478==    by 0x8157AA4: PyNode_AddChild (in /usr/bin/python2.6)
> ==15478==    by 0x8157EBE: PyParser_AddToken (in /usr/bin/python2.6)
> ==15478==    by 0x805E81E: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x80FAE9E: PyParser_ASTFromFile (in /usr/bin/python2.6)
> ==15478==    by 0x80F0321: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x80F1520: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x80F179F: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x80F1D75: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x8269003: ??? (in /usr/bin/python2.6)
> ==15478==
> ==15478== 1,572,864 bytes in 1 blocks are still reachable in loss record 2,588
> of 2,588
> ==15478==    at 0x4025018: malloc (in /usr/lib/valgrind/vgpreload_memcheck-
> x86-linux.so)
> ==15478==    by 0x808E8E3: ??? (in /usr/bin/python2.6)
> ==15478==    by 0x809E61A: PyString_InternInPlace (in /usr/bin/python2.6)
> ==15478==    by 0x80921C2: PyDict_SetItemString (in /usr/bin/python2.6)
> ==15478==    by 0xA2A8ACD: ??? (in /usr/lib/python2.6/dist-packages/sip.so)
> ==15478==    by 0xA2A8E9E: ??? (in /usr/lib/python2.6/dist-packages/sip.so)
> ==15478==    by 0xA2A8FF4: ??? (in /usr/lib/python2.6/dist-packages/sip.so)
> ==15478==    by 0x80D7035: PyEval_EvalFrameEx (in /usr/bin/python2.6)
> ==15478==    by 0x80DBB26: PyEval_EvalCodeEx (in /usr/bin/python2.6)
> ==15478==    by 0x80DBC36: PyEval_EvalCode (in /usr/bin/python2.6)
> ==15478==    by 0x80F0128: PyImport_ExecCodeModuleEx (in /usr/bin/python2.6)
> ==15478==    by 0x80F047B: ??? (in /usr/bin/python2.6)
> ==15478==
> ==15478== LEAK SUMMARY:
> ==15478==    definitely lost: 700 bytes in 12 blocks
> ==15478==    indirectly lost: 766 bytes in 34 blocks
> ==15478==      possibly lost: 1,368,637 bytes in 644 blocks
> ==15478==    still reachable: 12,846,296 bytes in 12,562 blocks
> ==15478==         suppressed: 0 bytes in 0 blocks
> ==15478==
> ==15478== For counts of detected and suppressed errors, rerun with: -v
> ==15478== Use --track-origins=yes to see where uninitialised values come from
> ==15478== ERROR SUMMARY: 13064 errors from 570 contexts (suppressed: 686 from
> 12)
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