RISC-V: NO_WARNING preferred else value for RVV

PR target/115840.

In riscv_preferred_else_value, we create an uninitialized tmp var
for else value, instead of the 0 (as default_preferred_else_value)
or the pre-exists VAR (as aarch64 does), so that we can use agnostic
policy.

The problem is that `warn_uninit` will emit a warning:
  '({anonymous})' may be used uninitialized

Let's mark this tmp var as NO_WARNING.

This problem is found when I try to build glibc with V extension.

gcc

	PR target/115840
	* config/riscv/riscv.cc(riscv_preferred_else_value): Mark
	tmp_var as NO_WARNING.

gcc/testsuite
	* gcc.dg/vect/pr115840.c: New testcase.

0 files changed, 0 insertions, 0 deletions