Don't use internal __CxxDetectRethrow: it has side effects

Since the __CxxDetectRethrow may increment __ProcessingThrow, which then
must be decremented in __CxxUnregisterExceptionObject, and the latter does
many other funny things with exception handling CRT machinery, we cannot
use those internal functions (neither alone, nor together), or we end up
breaking runtime's expectations: the runtime code checks __ProcessingThrow
left and right, expecting its non-0 value to indicate "we are unwinding...
possibly called from a dtor()". In this case, e.g., std::current_exception
returns nullptr inside catch block.

This creates our own copy of __CxxDetectRethrow, which does not mangle the
global state, and just performs the same checks. This is a dirty hack, and
it relies on current layout of the exception description layout - so must
be synchronized in the event of changes!

Change-Id: I2c475fbc2468073b796c7e9d0f4dfcd315896489
Reviewed-on: https://gerrit.libreoffice.org/58730
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

0 files changed, 0 insertions, 0 deletions