build: Fix float endian configure test when using clang -O4

When using clang -O4, the compiled test object is output in bitcode
format rather than as an ELF object, so when we grep the test value from
the object it fails.  To work around this, go ahead and link the test
object into an executable, and then grep against this native binary
instead of the compiler's intermediary object.

We need to add __attribute__((used)) to ensure the d variable doesn't
get optimized out during linking, since it's not referenced in the
test's main().

Patch authored by cmuelle8 <abendstund@gmail.com>

Reviewed-by: Bryce Harrington <b.harrington@samsung.com>
Bugzilla:  https://bugs.freedesktop.org/show_bug.cgi?id=63310

0 files changed, 0 insertions, 0 deletions