-Wdeprecated-copy does not exist in Clang 6.0.0
in MR !786 (merged), the line
#pragma GCC diagnostic ignored "-Wdeprecated-copy"
has been added to several files to filter warnings, in particular coming from Shark and Ossim includes.
../Modules/Core/Transform/src/otbSarSensorModelAdapter.cxx:31:32: warning: unknown warning group '-Wdeprecated-copy', ignored [-Wunknown-warning-option]
In particular in CI we still use an old version of clang (6.0) to compile OTB, resulting in this warning.