tree 9b100e0dbd1de6589f13db155332e6560b7a1d48
parent e15c08c681ff00dc3e270c9c0ad737e086abfd76
author Dan Albert <danalbert@google.com> 1477692849 -0700
committer Dan Albert <danalbert@google.com> 1477692849 -0700

Support `-fno-exceptions`.

The only thing preventing the non-exception portions of GSL from
being used with `-fno-exceptions` is `gsl::narrow`. If we allow the
`-fno-exceptions` case to terminate with `gsl::Ensures` instead, the
library becomes usable in this case.

Note that AFAIK we can only automatically detect this case for Clang.
Non-Clang users will need to define `GSL_NO_EXCEPTIONS` themselves
when building.

Test: Made a test program using gsl::narrow, built and ran with and
      without -fno-exceptions. Can't add a test because unittest-cpp
      doesn't seem to support seem to support death tests, but `ctest`
      still passes for the default (`-fexceptions`) case.
Bug: http://b/24296825

Change-Id: Iae72dda03dbd82452fcc296897c73b913a54846a