Core_DFT complex test fails

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One of the tests that keeps failing when I enable IPP is the Core_DFT.complex test. Maybe this is a bug, a compiler issue or something else? Note that just disabling IPP is enough to make the test pass.

Setup:

• OpenCV 2.4.5
• OS: Linux (and Windows)
• Build with IPP 8.1.1 (full version)
• Compiler: GCC 4.4.7
• Proc: Intel Core i7-3770

This is the output of the test under Linux:

[ RUN      ] Core_DFT.complex_output
actual:
[1107, 0, 21.260571, 11.228176, 10.037194, -8.9082355, -11.504125, 5.5739045, -17.712776, 9.1467628, -17.712776, -9.1467628, -11.504125, -5.5739045, 10.037194, 8.9082355, 21.260571, -11.228176;
  0, 0, 3.0655251, -32.619347, -1.7245388, -1.591939, 2.060123, 15.305433, -10.024876, -19.287296, 45.652641, 4.7507696, 30.059517, -4.4938917, -6.1991448, 1.366415, 19.807344, -14.456347;
  0, 0, 11.842458, 7.1720943, -16.67252, -12.976288, -2.1442814, 7.4254756, -28.331766, 26.277344, 26.779587, -19.959454, 22.993725, -3.2826869, 18.621082, 22.677366, 19.48292, -9.0227509;
  0, 0, 0.44020176, 31.968536, -13.68578, 3.6858072, 7.0887933, 6.2630043, -47.50103, -0.79230404, -18.884607, 11.683279, 17.999392, -15.858835, 2.5650215, -1.7414846, 19.246815, 32.772125;
  0, 0, -14.371378, -5.3003192, 17.907524, -6.0550251, -4.2048216, 1.6760466, -21.973286, 9.2392521, -18.147696, -23.30809, -1.3073893, 8.1714888, -5.9584594, 18.174168, -24.069769, -12.901531;
  0, 0, -24.069769, 12.901531, -5.9584594, -18.174168, -1.3073893, -8.1714888, -18.147696, 23.30809, -21.973286, -9.2392521, -4.2048216, -1.6760466, 17.907524, 6.0550251, -14.371378, 5.3003192;
  0, 0, 19.246815, -32.772125, 2.5650215, 1.7414846, 17.999392, 15.858835, -18.884607, -11.683279, -47.50103, 0.79230404, 7.0887933, -6.2630043, -13.68578, -3.6858072, 0.44020176, -31.968536;
  0, 0, 19.48292, 9.0227509, 18.621082, -22.677366, 22.993725, 3.2826869, 26.779587, 19.959454, -28.331766, -26.277344, -2.1442814, -7.4254756, -16.67252, 12.976288, 11.842458, -7.1720943;
  0, 0, 19.807344, 14.456347, -6.1991448, -1.366415, 30.059517, 4.4938917, 45.652641, -4.7507696, -10.024876, 19.287296, 2.060123, -15.305433, -1.7245388, 1.591939, 3.0655251, 32.619347]
reference:
[408.87067, 0, 21.260571, 11.228176, 10.037194, -8.9082336, -11.504125, 5.5739045, -17.712776, 9.1467628, -17.712774, -9.1467638, -11.504125, -5.5739045, 10.037194, 8.9082355, 21.260571, -11.228177;
  -14.131784, -18.597652, 3.0655251, -32.619347, -1.7245378, -1.5919371, 2.060123, 15.305433, -10.024876, -19.287296, 45.652645, 4.7507715, 30.059517, -4.4938912, -6.1991448, 1.366415, 19.807346, -14.456347;
  27.154518, -1.079195, 11.842458, 7.1720943, -16.67252, -12.976286, -2.1442814, 7.4254756, -28.331766, 26.277344, 26.779585, -19.959454, 22.993725, -3.2826872, 18.621082, 22.677366, 19.48292, -9.0227509;
  -26.897911, -2.7036204, 0.44020176, 31.968536 ...