make OUString(OUStringLiteral) constructor constexpr

with the intent that we can declare
static const OUStringLiteral FOO = "bar";
static const struct {
OUString s;
} xxx = { FOO };
and have the xxx laid out at compile time.

Kudos to mikekaganski for coming up with the idea of using
the rtl_uString struct inside OUStringLiteral.

We are using a union to defeat the array bounds checking
that the compiler does when it evaluates constexpr values,
so this might be brittle.

Change-Id: I9a6247a17afab2eb28df139d532a8d864c49cd62
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/114196
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

0 files changed, 0 insertions, 0 deletions