Description of problem:
xtl tests fail on ppc64le. It used to work on F29 with gcc 8, but some gcc 9 optimization seems to have broken things.


Version-Release number of selected component (if applicable):
xtl-0.6.4


Actual results:
[ RUN      ] xfixed_string.insert
/builddir/build/BUILD/xtl-0.6.4/test/test_xbasic_fixed_string.cpp:519: Failure
Expected equality of these values:
  s.c_str()
    Which is: "operation"
  "opebration"
[  FAILED  ] xfixed_string.insert (0 ms)
[ RUN      ] xfixed_string.erase
[       OK ] xfixed_string.erase (0 ms)
[ RUN      ] xfixed_string.append
unknown file: Failure
C++ exception with description "Invalid size (17) for xbasic_fixed_string - maximal size: 16" thrown in the test body.
[  FAILED  ] xfixed_string.append (1 ms)
[ RUN      ] xfixed_string.operator_append
/builddir/build/BUILD/xtl-0.6.4/test/test_xbasic_fixed_string.cpp:675: Failure
Expected equality of these values:
  s.c_str()
    Which is: "opea"
  "operationa"
/builddir/build/BUILD/xtl-0.6.4/test/test_xbasic_fixed_string.cpp:682: Failure
Expected equality of these values:
  s.size()
    Which is: 6
  size_type(11)
    Which is: 11
/builddir/build/BUILD/xtl-0.6.4/test/test_xbasic_fixed_string.cpp:683: Failure
Expected equality of these values:
  s.c_str()
    Which is: "operab"
  "operationab"
/builddir/build/BUILD/xtl-0.6.4/test/test_xbasic_fixed_string.cpp:689: Failure
Expected equality of these values:
  s.c_str()
    Which is: "operatabc"
  "operationabc"
[  FAILED  ] xfixed_string.operator_append (0 ms)


Expected results:
Tests should pass.