With PR #107223 and PR #107403, ASan testing can be enabled on SPARC.
This patch does so, 32-bit only on both Solaris and Linux. There is no
64-bit support even in GCC.
Apart from the obvious CMake changes, this patch includes a couple of
testcase adjustments necessary for SPARC:
- In `asan_oob_test.cpp`, the `OOB_int` subtest needs to be disabled: it
performs unaligned accesses that cannot work on a strict-alignment
target like SPARC.
- `asan_test.cpp` needs to disable subtests that depend on support for
`__builtin_setjmp` and `__builtin_longjmp`.
- `zero_page_pc.cpp` reports `0x5` as the faulting address on access to
`0x4`. I don't really know why, but it's consistent between Solaris and
Linux.
Tested on `sparcv9-sun-solaris2.11` and `sparc64-unknown-linux-gnu`.